spock is my friend

Kirk can’t have long term romantic relationships because he is Captain. He refuses to get with people on his crew who he has direct control over (in the context of Spirk I believe that this would also cause him to hesitate in forming a relationship with Spock) and of course all other relationships would be long-long-long distance.

Jim’s romances are also often ruses; it’s not often that he seems to truly fall in love with a woman as opposed to simply seducing her in order to gain an advantage.

Jim has to be forced by Spock and McCoy to relax; he also seems to have told no one about either his traumatic experience on Tarsus IV, or his traumatic experience with the spooky evil fog. This seems to me to show a reluctance to show weakness.

Jim loves his position as captain and would do (almost) anything to maintain it.

I also see Kirk as fairly calculating; he is able to put emotion aside to make difficult choices (as in The City on the Edge of Forever). Kirk, while personable, is a fairly Vulcan human.

All of these things, I believe, show that Kirk probably feels lonely and alienated. I think this is why he understands Spock so well — they are able to find in each other the solace they lack everywhere else. Kirk can trust that Spock won’t be manipulated by him because of Spock’s Vulcan strength and logic; Kirk doesn’t have to worry about Spock attempting to gain power because Spock does not want command.

Crewman: “He’s out there with the other Vulcans. He told us to wait in the shuttle.”