I'm so confused

This is gonna start off elementary school-ish but please bare with me. So there is this guy that I liked in 6th grade while he was in 8th. Well he went to high school and the feelings for him faded. Fast forward a few years. I'm now a sophomore and he is now a senior. My feelings are back, and this is were it gets kind of complicated. So we started having really great conversation one night and that's when I regained my feelings. Well things escalated a bit and we ended up sneaking out and I gave him a blowjob and he fingered me. Now he's the 1st guy that I've ever experimented with so I think that's why I'm a little more attached and attracted to him than I usually am to other guys. But we both had some fun that night and I like him more after that well here's the problem. He got back together with his ex like 3 days ago and he is stil wanting to be sexual with me. He has a history of cheating and everyone knows it. But I don't really know what to do and I was wondering if anyone could give me a few words of advice. Because aside from the cheating (which I know is a HUGE red flag) he has a lot of great qualities and I just think I'm gonna end up hurt again and I need help from people who can see what I can't and who have maybe been through something like this themselves.