How do I respond when im at a loss for words?

30F (me) 29M (him)

TLDR: he was an asshole, wants me back, and im at a loss for words on how to respond

Backstory is I’ve been dealing with this guy for 1.5 years. We live on the opposite side of the state so seeing each other involves me traveling to him or occasionally I join him on a work trip elsewhere. I’ve gone above and beyond for him and was always there for him including the worst times of his life. He holds me in high regard for that reason. He works in the entertainment industry and is constantly getting beautiful women thrown at him. Issue is We went on a trip to NYC where he was “working/networking” and he left me at the hotel all day/night for 5 days only coming back to sleep at 5am and getting breakfast with me then leaving at 11am. Final straw was one night I went out with a friend and ended up stranded, I needed him to call me an uber at 4am. He ignored my 100+ calls asking for help despite the fact he actually was 2 blocks from me at that time! The next day he said I put myself in that situation so he wasn’t gonna get me out of it. I was crying on the side of the curb, he had my location and knew I was 2 blocks from him but instead I had to have A stranger called me an uber and I made it home around 4:30am. He texted me at 440 saying “damn you took me off the room? Bet” I NEVER took him off the room so I think this was a lie because he never came back to the room that night. Plus he had a key so he can enter even without being “on the room”??? Such a stupid lie. He never came back till 3pm the next day. Clearly I assumed he cheated on me and went home with someone else. I packed all his shit and said we’re done. When he returned to get his stuff he pleaded his case as to how he didn’t cheat etc etc. I didn’t want to fight so I eventually accepted it. When I got home from the trip I found out I was pregnant. I had time to reflect and I told him I knew he cheated and I was getting an abortion. Partly I was hoping he would show some compassion. He basically said have a nice life and fuck you too. I respectfully wished him a nice life and said he’s not what im looking for in a partner as he’s not ready for a serious committed relationship. Few days went by and he started calling and texting me saying he misses me so much and he’s sorry for everything, that hes losing his mind. I know he feels like this because im the only person who was there for him at rock bottom, but he was never there me ever. I’ve ignored everything because I honestly don’t know what to say, like what’s he even sorry for if he’s denied all the accusations?

I need help on what to reply back (it’s been 4 days). Im thinking “I hope you find what you’re looking for” because I want to show him I really don’t care anymore (I still do a little). I want to say something that hits hard