+2
he sounds like an ass tbh
but yeah, just ask him bluntly if his pulling away had anything to do with your transition. and that you wish it was the way it used to be and don't understand why things changed. also, say something like 'every time i try to broach this topic it never goes anywhere, and it's really been on my mind, bothering me... especially when i don't hear from you for months and then you out of nowhere text me pics of your new car.'
of course, that could just make him pull away even further, but... at least then you'll pretty much know the reason, right?
Steel is right about having many best friends over the course of your life/people drifting in and out over the years. whenever this sort of thing happened to me, i've had a hard time letting go of those people too. it takes time to get over stuff like that, but you should take his response at face value and try to accept that this is how it is now. maybe you don't want to be friends with someone who can't be there for you when you really needed them, you know?
anyway, i'm sorry that happened to you.