AITAH if I break up with my boyfriend over fanfiction?

My (24F) boyfriend (25M) have been dating over five years yet I'm worried this might be the straw that breaks the camel's back.

A little bit of context. I've been writing self insert fanfiction ever since I was 10 years old as a coping mechanism, it's cringy, self indulgent and private, but I've never prioritized that over my relationship with my boyfriend.

A couple of weeks ago he asked me to stop writing stuff like this but wouldn't tell me why, he just gave me an ultimatum, either I stopped or we were over.

We sat down and had a conversation, he specially had an issue with a character from the game Mortal Kombat 1 (Bi-Han/Sub-Zero). He told me that he was feeling insecure and that he kept wondering if I was thinking about him while we were together. I reassured him it wasn't the case and agreed to stop writing self insert fanfiction, since a virtual character wasn't really worth throwing the relationship away.

Now, I don't only write self insert fanfic, I also write regular fanfic about the characters I enjoy and he's fully aware of this, he follows me both on Tumblr and AO3 where I post my fanfiction.

Yesterday he came up to me and ask me to delete a fanfic I had been writing about Bi-Han exploring his character pre-MK1, I had stopped updating and writing said fanfiction after we had this conversation because I didn't want him to think I was still obsessing over him.

When I explained that to him he said that wasn't good enough, I also offered the option to orphan my work on AO3 (for those who don't know, AO3 allows you to orphan a story so it's no longer in your account but people can still read it) and that still wasn't good enough.

Turns out he was insecure about this character but for a whole other reason.

See, my fanfiction had started to gain some traction in the fandom, I'm not saying big numbers but it's becoming quite popular. Now, my boyfriend is a writer too, he just mostly writes for his own characters and I've always supported his work.

It turns out that he's jealous about my fanfic being popular, he even said it was "mediocre" and it was only popular because of "teenagers simping over the bad guy".

He's giving me the cold shoulder now and I'm really thinking about breaking up with him and going back to my home state. I know he wouldn't be able to afford rent on his own while I have my own place back home but I can't help but feel disgusted at his behavior.

AITAH if I left him over fanfiction?