My brain sucks, anyone have similar experience?

I have been getting retroactive jealousy triggers at the most random times. I am in a long term relationship, have been for almost a year now.
Earlier on in the relationship is when i realized i had retroactive jealousy for the first time. Just through conversation I realized that she was a lot more promiscuous than I imagined (not that it’s my business). It was before me and I know that she is loyal to me, just by getting to know her. I have gotten the mental movies and intrusive thoughts for a while at the beginning but I haven’t had any of these for a while until lately. If i watch porn specifically i get random intrusive thoughts or mental movies and i hate it. It even happens when I am having sex with her sometimes. Its so frustrating because i have been pretty good unless i am doing these two things.
Anyone else have this experience?