Sounds Avoidant. Which usually has PTSD thrown in the mix somewhere.

I'd suggest not trying to figure out what happened with him. It happened, and probably if you had gotten together, it would have continued to happen that way. Imagine if he had behaved that way after you had slept together. Now it's confusing and annoying, then it would have been devastating. You dodged a bullet.

The thing is to try not to let your trust of your own instincts take a knock. This oddball behavior is not the norm. Don't expect the next guy will flake out on you. But, now you know: if this is the behavior pattern, expect this ending. Hopefully there won't be a next time, but if there is, recognize it and nip it the bud sooner.