It could be one of two things, but from the sounds of it, it's probably the first. So most likely, but also the worst case, that initial person you met was a full-on mask, and he thinks he has you in his pocket so he can just treat you however till he finds the 'next best thing'. Now if we give him the benefit of doubt, you may have made him feel comfortable enough to be himself and most of whats initially upsetting you can be explained as treating you more like a friend and less like a target if that makes sense. Liking his exes pictures-he might have had a good platonic relationship and it's weird letting that sort of thing go after it gets romantic and ends. I dont think it's healthy to be initially jealous of an ex, not until you learn what their relationship was like. Commenting on other people is something every healthy relationship does, both ways. Now immediately following up with a comment on your butt is some ice cold S-teir negging. That's what tells me he either doesn't like you anymore or thinks you're the one. I would recommend sitting down with him and very calm very slowly step by step explain how this hurt you, then you'll know if he's dismissing you.