The relationships of Kanan Jarrus in Star Wars Rebels.
Romance
Hera Syndulla
Kanan met Hera at the planet Gorse and its moon Cynda and revealed himself to be a Jedi, instructed her to keep his secret approximately six years prior to the events of Star Wars Rebels. Hera along with Zeb, was initially the only member of the crew of the Ghost who knew Kanan was a Jedi until the events of "Spark of Rebellion". When Kanan planned to go to Malachor with Ezra and Ahsoka to seek knowledge on to defeat Darth Vader and the Inquistors, Hera was worried she might not see Kanan or Ezra despite Kanan reassuring they will come back. Eventually, Kanan and Ezra managed to return to the rebel base, but without Ahsoka, and Kanan embraced Hera once he reunited with her.
Over time, Kanan developed romantic feelings towards the Twi'lek rebel general. Hera would eventually admit her love for him in return. Before his death, Kanan stopped Hera from getting killed and when his sight was miraculously restored, he looked at Hera one last time. After his death, Hera honored the sacrifice of the man she loved by adding him to the Kalikori, symbolically making him a permanent part of the Syndulla family clan. Hera eventually gave birth to their son, Jacen Syndulla, who was born with his mother's flying skills and later on his father's Force abilities.
Friends and allies
Yoda
Like all Jedi, Kanan deeply respected Yoda and was trained by him as a young boy; prior to Kanan becoming Depa Billaba's apprentice.
Mace Windu
Although Mace and Kanan rarely interacted with each other, Kanan held a great deal of respect for the Jedi Master, reflecting on his heroics during the Battle of Ryloth with Cham Syndulla.
Depa Billaba
At some point, back to when he was known as "Caleb Dume", Kanan was assigned to Depa as her apprentice. It can be assumed that the two had a good relationship, though according to Kanan, she was more strict as a teacher than he was. They fought side by side during the Clone Wars. Depa sometimes gently teasing him about his habit of asking many questions.
During the execution of Order 66, when clones they fight alongside with turned against them, the two fought back in self-defense, but Depa soon realized that they are vastly outnumbered by the Clone Troopers of their unit. She ordered her apprentice to run while she held them off, but was quickly gunned down by Commander Grey and the rest of the men who once served under her command. Her death would leave Kanan scarred with grief and guilt because he escaped and she did not.
Depa's death is one of the main reasons why Kanan was initially distrustful and hostile towards clone troopers; like Rex, Gregor, and Wolffe, despite the fact that they removed there inhibitor chips before Order 66 initiated, as well as the fact that they were not a part of the Jedi Purge. However, after working with Rex in saving Ezra Bridger Commander Sato, and his crew, Kanan finally put his animosity towards the Clone Troopers behind him and seemed to forgive them for their in his master's death.
Initially, Kanan did not fully understand Depa's belief that the Jedi have to be willing to sacrifice themselves for the sake of others, until he allowed himself to be captured by the Empire on Lothal so the other rebels could escape. Kanan continued following Depa's teachings as he trained his own apprentice, Ezra, but wasn't as strict as Depa was to him. Upon returning to Lothal in order to liberate from the Empire's control, Kanan now came to acknowledge Depa's belief of self-sacrifice where he gave up his own life to not give the Empire a disadvantage, but to save his fellow rebel allies.
Garazeb Orrelios
Kanan gets along with Zeb very well but there's still occasional friction that's positive or negative, despite this, they are good friends, Zeb, along with Hera, was initially the only member of the crew of the Ghost who knew Kanan was a Jedi until the events of Spark of Rebellion.
When Hera was rescued from Governor Pryce, Zeb was devastated to hear that Kanan had been killed during the rescue mission where he and Ezra shared a sad embrace to comfort each other. Zeb sought to avenge Kanan where he discovered Kanan had died to not only to save Hera, Ezra, and Sabine, but to bring a severe blow to the Imperial military production on Lothal. Later, Zeb tried to kill Thrawn's personal assassin, Rukh to avenge Kanan, but he was stopped by Sabine who told him that Kanan would never want him to commit murder.
Sabine Wren
Sabine looks up to Kanan due to his leadership skills and abilities, and shares a daughter-father bond with him.
It has been shown that Sabine gets annoyed by Kanan, calling him frustrating. But, when Kanan was captured by the Empire, Sabine showed that she was willing to go to the extreme to save him. The one thing they agree on, is helping Ezra through his troubled past. Sabine's Mandalorian heritage can often clash with Kanan's teachings where they disagreed on whether to negotiate with Fenn Rau peacefully or use brutal force to convince the Protectors of Mandalore to let the Rebels have safe passage through the Concord Dawn system. However, after both of their attempts failed, they managed to succeed in gaining passage for the Rebels after taking Fenn Rau and having him join the rebellion.
After Sabine discovered the Darksaber on Dathomir, Kanan believed Sabine could use it in order to persuade the Mandalorians into joining the rebellion. Though reluctant, Sabine agreed to be trained under Kanan and Ezra to learn how to use the Darksaber. However, the training does not go well as Sabine's persisting frustration at the expectations of wielding the Darksaber thrust upon her starts to gnaw on Kanan's own patience, creating tensions between. After Kanan had a pep talk with Hera, he and Sabine apologize to one another and begins training again with Sabine wielding the Darksaber for the first time. As they kept training, Sabine finally revealed to Kanan how she was estranged from her family and broke down in tears, leaving Kanan to comfort her where he also revealed he would support her in any path she chose to follow.
When Kanan was killed after they rescued Hera from Governor Pryce, Sabine was devastated and wanted to get revenge for the Empire. However, Sabine realized that Kanan not only died to save her and her friends, but to bring a severe blow to the Imperial military production on Lothal. Later, when seeing Zeb angrily beat up Rukh to death, Sabine stopped him as she realized that Kanan would never want them to commit murder, where they spared Rukh's life and spray-painted him.
Ezra Bridger
Shortly after Ezra joins the crew of the Ghost, Kanan becomes his mentor, training him in the ways of the light side of the Force. Throughout their time together, Kanan comes to see Ezra as a son or little brother-figure. Despite his respect for Ezra, they do not always agree with each other; like when Kanan is initially unwilling to trust Rex, due to the role the Clone Troopers had in wiping out most of the Jedi Order. Kanan would become proud of Ezra for mastering his abilities and Ezra would thank Kanan for not just teaching him to be a Jedi, but to be a better person.
When Kanan was killed after they rescued Hera from Governor Pryce, Ezra was overcome with grief and sadness over losing his master, friend, and father-figure.
C1-10P
Like the other members of the crew of the Ghost, Kanan does not get along with Chopper at all, due to his selfish nature and constant pranks, as well the fact that he has put the Ghost crew lives in danger more than once.
When Kanan was killed after they rescued Hera from Governor Pryce, Chopper was devastated and comforted Hera where he convinced her to add Kanan to her Kalikori so he would always be an honoree member of her family.
Ahsoka Tano
Kanan met Ahsoka when she rescued the Ghost crew from the Empire on Mustafar. It is currently unknown if Kanan and Ahsoka knew each other during the Clone Wars. During Vader's raid on the Rebel fleet, Ahsoka asked Kanan too help her find out who was in the TIE Fighter, where Kanan asked how he could help, which Ahsoka responded with "Just remember your training". After Ahsoka found out that Vader's her former mentor, she fainted in Kanan's arms with him deeply concerned for her safety.
In "The Future of the Force", Kanan asked about Ahsoka when she was fighting the Inquisitors, shown that he's worried about her and was the first one to suggest that they couldn't leave her.
Kanan was saddened when Ahsoka sacrificed herself to give him and Ezra more time to escape from Darth Vader.
Rex
Kanan was initially distrustful and hostile towards Rex and his fellow clones due to the events of Order 66. When they went undercover as stormtroopers to rescue Ezra, Commander Sato, and his crew, they managed to work together well in a way reminiscent of the Clone Troopers and their Jedi Generals during the Clone Wars. After this, Kanan finally put his animosity towards clones behind him when he gave Rex a salute of respect, which the captain gladly returned.
Cham Syndulla
During the Clone Wars, Kanan heard about Cham from Mace Windu, who spoken highly of the Twi'lek. When they first met, Kanan tries to impress Cham and appears to enjoy listening to his stories. However, like the other rebels, Kanan was used and turned on by Cham and his warriors. At the end, they are shown to be on good terms.
Acquaintance
Obi-Wan Kenobi
Kanan had a Jedi Holocron that contained Obi-Wan's message; regarding the fall of the the Republic and that the surviving Jedi must go into hiding until the time was right for them to come out of exile, it is unknown if the two had met or knew each other. Like many of the surviving Jedi, Kanan believed Obi-Wan was killed in the Jedi Purge (due to the fact that the surviving Jedi were unable to contact each other, as they have gone into hiding). In "Visions and Voices", Ezra Bridger learned via a Nightsister ritual, that the means to defeat the Sith was "Obi-Wan Kenobi". Kanan was surprised to find out that Obi-Wan was still alive and referred to him as "Master Kenobi", implying that Kanan only knew the latter through his reputation.
Enemies
The Grand Inquisitor
Kanan and the Grand Inquisitor became enemies from the moment they met. In their first confrontation, the Grand Inquisitor was unimpressed by his skills, but the more they clashed, the more he found Kanan to be a worthy opponent; in their final confrontation, when Kanan found his resolve, both the Grand Inquisitor and the Jedi gave each other a salute of respect. Upon being bested and deprived of his weapon, the Grand Inquisitor was shocked to be defeated though he warned his conqueror of what the Jedi's actions had unleashed before taking his own life.
Despite them being mortal enemies, Kanan was visibly shocked by the Grand Inquisitor's taking of his own life and in fact felt unconscious regret for not having attempted to save him.
Anakin Skywalker/Darth Vader
During the Clone Wars, Kanan sensed strong emotions of anger, rage, and hatred, implying that he had crossed paths with Anakin once or twice. When Kanan is about to fight with Vader, he senses a cold feeling when Vader arrives or is nearby; he initially assumes it is another Inquisitor, but to his horror, he deduces Vader is not an Inquisitor but a Sith Lord; due to how powerful the latter's connection to the Force is, and was injured in the battle that followed their confrontation. When Ezra wanted to fight him afterward, Kanan told him Vader was too powerful and that the only reason they were still alive was that he was playing with them.
In "Shroud of Darkness", It is revealed that Kanan greatly respected and admired Anakin, telling Ezra he was the greatest warrior the Jedi had during the Clone Wars.
Darth Maul
Kanan did not trust Maul even though Ezra insisted the former Sith Lord was on their side, and only tolerated Maul when Ahsoka (reluctantly) agreed they could use Maul's aid.
But once Maul made his true intentions known, that he intended to take Ezra away from him, he struck Kanan with his lightsaber, blinding him, and would have killed him had Ahsoka not defended him. Kanan remembered his Jedi training, trusted his senses amplified by the Force, and not only bested Maul, but thwarted his plans by sending him falling over the edge of the Sith Temple.
When Kanan met Maul again in order to give him the Sith holocron in order to save his friends, Maul told Kanan he never attempted to blind, but Kanan had already known that Maul attempted kill him back on Malachor. With that stand, Maul attempted to kill Kanan again by ejecting him out into space, but Kanan managed to survive by using his Force abilities to save himself from being suffocated.