Why does he beg to be in my life but continue to mess up?

So I knew this guy since 2019 and I keep trying to let him go because everytime he has my attention he mentions other girls to me, says he love me so much and then like 2 days after I let him back in my life he tells me about other women and how much he miss his ex. Then when I block him and I even changed my number he still found out my back up numbers and text me and begg for me to take him back he says he loves me so much. He even says sorry and then the cycle repeats he just use me to vent about the last girl he was with when I thought he was going to ask me out or something. Then he said he wants me in his life, and he loves me. I just feel like it’s a game and yes I realised he really doesn’t want me or love me. Idk why he would do this to me for almost 4 years.