Can you advise me on my emotionally abusive ex?

I’ll try to keep this as short as possible. Before I finally broke up with my ex final, which was 4 weeks ago… he was abusive towards me and incredibly selfish. He was stingy, blamed me for everything, we even went to counseling and he accused me of “not sticking up for him.” Sure he had some good qualities, but mostly only with words and sweet talking. That is always what pulled me in. He also made me believe our arguments were always my fault and would say things like, “I’m not talking to you unless you say sorry,” and if I didn’t say the first word to him he would ignore him until I did. He disrespected my friends and family as well.

Ever since I broke it off permanently, and he’s now realizing it is serious and not just another break up and get back together in a few hours, he has been messaging me saying how sorry he is and how he’s had realization of how much of a jerk he was to me and wants one last chance to show me. I had to put a no contact order on him when I first broke up with him because I didn’t trust him to stop hurting me, initially he responded “I will NOT be dumped,” and e-mailed my parents saying that I “didn’t know that love is unconditional.” etc etc.

I don’t know what to do, I don’t know what my gut feeling is or if I am just fooling myself. I want to believe he is sincerely sorry and wants to change, but I’m scared that if I go back to him it’ll be the same nightmare repeated but worse. There has been so much hurt as well, how am I to get over all those times of pain?