So shortly after our break up, my ex fucked another girl. He wants to work things out and I'm on the fence. Has anyone been in this situation, reconciled, and the relationship is going great? Or is this too idealistic?

UPDATE/EXPLANATION

We broke up over something stupid but it led to a really scary situation. I wanted to break up with him but he started yelling how I couldn't leave his apartment and he would not open the garage door for 1 hour. He kept yelling at me to call 911 because he wasn't going to lete leave but he said it in a way that made me not want to call, "You made this breakup ugly so I'm going to make it uglier. Call the cops!" I just stood there crying and texting friends. He tried to take my phone. An hour later of me begging to leave he tells me the gate was opened the whole time. I grabbed my bags and ran. I fell because this was a new place it was dark, and I ended up spraining my foot and my other leg was bleeding. He told me it's a sign I shouldn't leave him. While he went to get towels, I took my bags and ran for my car. The gate was never opened. I cried while locked in my car until he let me out. That is our breakup story for anyone asking. It continued with hkm gaslighting me saying I caused him to act like that, to him crying and apologizing, to him fucking another girl because he thought I was out fucking another guy.