Why does the guy I had a thing with start putting me down in front of other people?

So, I'm in a friendgroup with like 8 people since 3 years. Two years ago I started noticing that one of my guy friends started having sexual interest in me. Back then it was completely fine, we always watched movies the whole night when the others slept at the sleepover. He made allusions, but it was never that deep and I was never the type to get involved in something like that, so it was fine. Last year then, we had a 3h talk at a birthday party outside on the street which really caught me off guard because he suddenly started asking me if we could kiss and stuff, complimented me on my personality after a really deep talk and and and. 4 months later we saw eachother again and we slept over together at a party and kissed at night. It was my first kiss too and he's very experienced. He was really different. We cuddled, he kissed my forehead and stuff and he said how special I was, that I was the prettiest girl in the world, but that he would be not good enough for me and that he doesn't know what he wants from me because stuff like that is not that easy for him. So after that night, he became cold and its not like before. A week after he sleept at my place, didn't try anthing tho, it was weird and he was very quiet. Now he ignores me in front of others or insults me, often so much that I'm really ashamed. Also very childish insults that no one laughs about. We made out one more time at night (I know, dumb) but now I decided to break contact from the group for a while because he kinda got my hopes up and let me fall again and it hurts because in the first place, we are friends but he doesn't act like it anymore.

What the f*ck does he want from me? I know he would sleep with me, but in my opinion this is not a normal act for a experienced guy who did that with other girls before to get me to do that. I don't get what his mission is, please help. by the way. keep in mind that he was often drunk during many conversations where he was more open and touchy.

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28 d
I talked with his best friend yesterday and he told me after 2 hours of talking that he selfsabotages this relationship, partly willingly. I already knew that he had really bad commitment issues but that proved that I was right. I took long to get that info out of him so I believe him, we're also close friends. Guess I overtaxed him lol because I know for a fact that I didn't imagine the feeling that there was a spark and that explains a lot now. I'll still take a break and see what happens.
Why does the guy I had a thing with start putting me down in front of other people?
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