friendship advice

i’ve been friends with this guy since we were 11 years old, when we got to high school he started telling me all his feelings for me and i thought it was sweet and stuff but i never was really interested in him. The more i denied him the angrier he started to get. But i could always kinda see where he was coming from bc i kinda had a thing with some of his friends. i finally decided to give him a chance in 2017(the start of our senior year) it was going fine but every time we kissed i just knew he wasn’t the one for me but i didn’t say anything and then one night at a party he started accusing me of having sex with his best friend which we have but it was in the past which he knew about but i thought he was over it, anyways after he left the party he was getting psycho and i started ignoring him until the next day i finally told him i couldn’t do it anymore i just didn’t feel the same way and ever since then we just haven’t been the same. he always been close with me but to this day he still tries to get with me even tho i constantly tell him no and i think he really is in love with me and i feel like a piece of shit for always rejecting him....should i give him one more chance? were both 18 now and i just feel like if we were meant to be together then we would be idk this has been going on for like 6 years now