Abusive ex wants to take me to file a police report for being assaulted by another guy?

TLDR: Got assaulted by another guy after abusive ex broke up with me. Told ex because I thought he’d find out anyways and he accused me of sleeping around. Now he’s trying to push for me to file a police report and says I need to treat myself better. He told people at work (and lied about it) and said it was in hopes someone would convince me to do it. He’s even offering to drive me to the station and wait in the car. I’m confused because he wasn’t like this (offering to do nice things) during our relationship so I don’t get why he’s like that now.

I was with my ex for 2 years and stepping back now I realized it was pretty awful. He yelled a lot, was controlling, extremely insecure, very unhappy person, everything was either his way or no way, played games, lied, he threw things at me a few times, etc. Ironically, HE broke up with ME a week and a half ago because it was “too toxic and he didn’t want toxic”. When I was hanging out with friends afterward, I got assaulted by this guy and have bruises down my arms. I work with my ex and they’re becoming strict on guidelines including uniform, which includes a short sleeve. So I figured he’d find out anyways so I started to tell him. At first he was supportive but then turned it into something about me having sex with someone else and how I “lied” saying I didn’t want to move on from him. So I didn’t tell him anything else. But now he keeps trying to talk to me about it. At first he was like “I kinda want you to file a report”, “I wanna know who it was”, etc. But now he’s trying to really push me to file a report. He told people at work even tho he said he wouldn’t and then lied. But he claims that he told them because he wanted someone to convince me to file the report and says he really wants me to make the report because he thinks I deserve better than how I treat myself. He even offered to go with me to the police station when I file it, even offered to sit in the car if I felt uncomfortable with him being involved. I just feel confused. He didn’t offer anything like this even when we were together so it doesn’t make sense. I keep wanting to believe that maybe he is a good person who just was dealt a shitty hand. But I keep remembering how he lied even now and try to remember that he’s not a good person