King Daniel Into Darkness wrote:
Some of The Lost Years is based on backstory from Gene Roddenberry's novelization of Star Trek: The Motion Picture, which was written concurrent to the film's production. It's a fascinating read, to see how the man himself imagined his characters and universe.
I have read TMP-book. It's quite short and very close to movie.
But, again, I didn't find any explanation for Spock's decision to reject his human half.
As for McCoy, he resigned from StarFleet due to his protest against Kirk's promotion. It's very good explanation.
In TMP Spock acts as a child, if he has no strong reasons to start Kolinahr.
This procedure is very similar to self-murder (he kills his half). And it's very similar to betrayal (towards his mother).