My (30f) boyfriend (35m) thinks I’ve cheated, wont believe I never have, keeps asking everyday and then trying to go back to normal. He says he is just joking.

We have been together for 8 or 9 months now, everythings been great for the most part except for his insecurities.

I’ve left exs before over their insecurities, but I find it naked to tell if this is something I should go ahead and cut him off over or something that can just be worked on if he puts in the effort.

About a month after we started seeing other we decided we would no longer see other people and agreed to that. We met at a bookstore and only he had dating apps, not me, I’ve never used them, not my thing.

But ever since he makes these semi light hearted cheating accusations? Examples;

We met up right after I finished at the gym and I had a sweat spot inbetween my thighs. He made a joke saying it was some other guys cum… ew. I told him that was gross, not funny, and I’d never do that.

If the passenger seat in my car is adjusted from his usual settings, he asks what guy I’ve been riding around with. Even though its adjusted for my dogs car seat… and he sees my dog in the car seat..

One time he asked me for a nude photo. I work in cybersecurity and grew up with the internet so its just something I have always politely refused to do. Risque or teasing, maybe, but never anything hot. He accused me of saving them all to send to another guy.

I got a promotion at work. He congratulated and hugged me, takes me out to dinner and brings me flowers and a book related to my career that I had my eye on. In the middle of me hugging him and saying thank you, he asks if I got the promotion from having sex with my boss.

The last one is the most recent, and I haven’t talked to him since it happened. Its been over a day, and I let him know I needed space. He said sorry and that he didnt think I would take it that serious as he is just joking.

I asked if he had an ex that cheated and he has like unresolved trauma or something and he said no. I told him that accusing me of doing something as pathetic and nasty as cheating directly questions my character, and I dont know if I want to be with someone who casually does that.

He has been sending lots of apologies, and my friends are saying I would be stupid to break up with him over it, saying its a small price to pay since hes a catch in other departments. But this doesn’t feel very small to me.

How do I make it clear to him that this isnt any ones category of funny, and it is an insult not a joke?

When he says these things I first feel disgust and then anger. The anger stops me from explaining or checking him about it, I just get quiet and bring it up later, and he says that not correcting him the moment is why it keeps happening.

But why would he even say something so weird in the first place?!

EDIT- I think I accidentally deleted this part BUT it is not just about me currently cheating on him either, he asks consistently if I have ever cheated on someone in the past. I have never done that in any capacity, besides maybe giving a number to a guy when my bf ditched me at a concert almost 10 years ago but I gave him a fake number while my bf of the time was watching so I dont consider that cheating at all.