Can he become that loving person he once was?

Me and my boyfriend (19) have been together for three years and over the last year he has blackmailed me to stay together for over €2000 for my “disrespect” each time has been for me calling him names or not doing exactly what he says when he says it or even after being hit and pushed and I’m not trying to be the victim, but I know that he is abusive. He pushes me away in the face regularly and always bruises me and pulls my hair and manages to turn absolutely everything against me and for some reason, even though he is the one that has hurt me I just want him to comfort me. Another part of me knows that the money he took off me is a lot and even more than I have right now and he lets me use one of his laptops and I feel if I was to let go he would take the laptop (that i feel i have technically paid for considering all the money he took) and if I didn’t give it to him, he would harm me or my home. I feel so trapped, he tells me that he doesn’t hit me (after he even hits me and if i mention what he did, he “ fines” me and takes €100 each time minimum.i only work part time and he took every cent i earned the last two months, he is affecting my mental health so bad and i know i have to let go but i can’t do it. He won’t let me go anywhere except for the shop the gym or work and even that has rules and now he even says i can’t paint my nails or read certain books or call him without asking ect.he has cheated on me three times at the start of our relationship and took down all photos of us recently.i feel like he has two different personalities what can i do