The truth is...
McCoy literally admitted on screen that he couldn't live without Spock.
☆☆☆☆☆
«I'm gonna tell you something that I never thought I'd ever hear myself say. But it seems I've missed you. And I don't know if I could stand to lose you again»
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Kirk literally didn't do that.
Kirk literally went on living—serving as an admiral, enjoying life and his laurels.
McCoy literally didn't do that. He literally couldn't move on. He pined for Spock.
The same thing happened when Spock left Starfleet for Kolinahr: Kirk continued to serve and pursue romances, while McCoy left Starfleet and let his life stagnate.
This is literally what we have on screen.
This is literally what the original Star Trek contains.
Nothing more, nothing less.
And this literally cannot be changed.
This is canon.
This is the original, primary Star Trek film universe.








