Yeah I have the similar symptoms and Im OCD. Today worse than usual! I got triggered by a particularly graphic photo. And now I cant get it out of my mind. And I feel by thinking of it, it is going to happen now to my partner. The anxiety is close to unbearable.

I have tried all of the techniques Zwangsstörung has suggested with no success. Pdoc wants me to start Clomipramine but I need to get off the zoloft first. Apparently it has been known to cure OCD. I am not keen to take the med, I would rather sort it out with therapy but that has been unsuccessful so far, and a lifelong cure is very tempting.

Goodluck with finding something to help, some people can get past these thoughts very easily, unfortunately I am not one of them. But Im holding out hope for you that you will be.