Should I give him another chance?

Anonymous
My ex and I broke up 2 months ago because of trust issues from the both of us. He was a gentlemen and he bought me stuff (basically just a good ass boyfriend all the way around and I was his first love). He met my family, told my mom how much he loves me. He even told me I was the best thing that ever happened to him.

I told him to ask her Y she cheated because that’s y he has trust issues and I have trust issues from previous guys as well, but he went over his ex’s house to ask her a question about y she cheated and she said “because she felt like it” and he thought automatically girls aren’t s**t and he just thought about everything that I did that made him feel like I don’t love him, then she manipulated him into having sex with her and he said f*** it and had sex with her for like 15 minutes, he said he didn’t enjoy it and he didn’t finish and stopped and left and told her “there is nothing between me and you, there’s no relationship or anything”. He’s a straightforward person for the most part.

He told me a few days after, he told me everything that happened “he felt guilty and regretted it and it was a mistake for doing that with her and he’s never doing it again, but he feels like he lost somebody that he loved (which is me) from doing that“ I thought he still has feelings for her because she was one of them exes that were crazy and he said “he doesn’t have feelings for her no more and he took the cookie and dipped” she still texts him after that but he doesn’t respond back.

I just wanna know what he was thinking, even though we weren’t together when he did it, I still feel it was low for him to do that especially if he was trying to work things out with me. He said he still wants me back, he just feels guilty for doing that with her. I respect him for telling me.

Today I had took him his belongings and he couldn’t even look me in the eye, or say anything to me. He looked so upset. He just took his things and went in the house. He’s still single also.
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Did he realize he messed up?
Should I give him another chance?
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