Guys who run for no reason?

Ok so I've known this guy for 3 1/2 years. Before he did not care about your feelings if he wasn't super into you. We had a mutual like before but I stopped talking to him after he did sexual things with another girl that same night we told each other. Yes we weren't together, but I found it really crappy. Especially when confronted, he lied about it. So I had blocked him and moved on.

Fast forward to now where we talk again and have confessed feelings once again, he's showed so many signs of change & that he cares about me. He has a fear I'll block him tho I've reasurred him i wouldn't. We've opened up to each other about personal things, we talk every day, call every week. It feels like a best friend & lover. Still not dating, but when i asked him what we are he said close individuals & we're past the friend stage. He tries to act nonchalant about getting my thoughts about kids & marriage... But now his ex girlfriend (that he swears wasn't his ex but I've seen proof) kept following him but he didn't follow her back & when I brought it up he said it was weird cause they barely talk. Now he's following her, has said nothing about it. So I'm pretty sure they talk more than he acted like. He also won't do something for me that I needed him to do & told him was important to me which makes me feel a certain way.

I feel very distraught because I thought he had changed from the lies & it seems like he's still this guy from the past I've tried to let go and move past. I know he wouldn't want to hurt me, so why is he acting so stupidly shady? It's like everytime he confesses deep feelings for me (like a week ago he slipped and said he wishes we were married) he distances himself or does something dumb. He's not the best at expressing himself because he gets nervous so I've tried to be patient but after seeing that it frustrates me. I'm not sure what to do anymore.
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1 y
I told him everything I was feeling & that I think that we should just be friends, but that i need some space for a while to be able to do that. He responded very kindly to everything I said and apologized if I felt like he was using me, giving me false hope, or being confusing. He said if I think that being friends is best then he's content with having me around occasionally when I'm ready... and I spent an hour crying 😓
Guys who run for no reason?
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