Could people change?

Chyna
So I am currently dating someone and he is literally like my other half. We act just the same, and we have an amazing time together. He's a big time high school varsity football player, so he has all the little high school hoes wanting him, but he shows that he wants me (+ he knows I'm crazy as hell and will fuck his ass up real quick!) I've been knowing him since my freshman year (I am currently a sophomore) and when I first met him, I wasn't a fan 😂 Anyways, as the year went on we got really close, and by being close I mean as in being really good friends. I was there to witness all of his shenanigans that he had with mulitple females at our school (He has a serious past I tell you). So when this past summer came, he told me he liked me and I confessed of my liking towards him as well, He literally stays next door to me so we started "talking" and he ended up giving me oral. I honestly felt like one of his victims so I ended things and he was very upset. He literally cut me off & I can say, I genuinely think I hurt his feelings. Once sophomore year rolled around, we didn't talk for about two months into the school year, and once we became back friends we literally started back up like it never ended. We really did miss each other, we had immediantly started back talking and started dating about a week ago. He seems to be taking us serious, he wants me to meet his mom, and he talks about marriage already, and he was the first to say "I love you." I'm just wondering if guys could really change or really like someone and act right? Because I really like him, but I don't want to end up like the rest of the girls he's hurt or used. Should I continue giving him a chance? Oh... and I feel like I'm ready to have sex, but I'm second guessing if I should do it with him. I'm going to be 16 on December 7th so. Please help.