Pure O replaying scene in my brain constantly all day

I have been diagnosed with OCD and have tried various medications that have not worked. The current focus of my obsessions is my boyfriend. He is my best friend, the person I truly believe is my soul mate, and the person I tell absolutely everything to. We are preparing for a big move in the upcoming months, and I think it has exacerbated my symptoms.

I am obsessed with checking and rechecking a sexual encounter he and I had in April of 2017. I had arrived at his apartment and told him that I was tired and I laid on the bed. I was wearing leggings so he went to initiate sex by pulling down on my leggings. I used my hand to stop him and he still kept pulling and I finally said “no” and he stopped immediately and gave me a rather surprised and offended look.

I told my therapist directly afterwards and he said “it sounds like he assaulted you.” I immediately became panicked and told him that’s not what I was trying to say at all and he said “come on alyssa, you know that’s —-“ and paused and waved his hand as if it was nothing. Then he said “it was probably just immaturity, I wouldn’t worry about it at all.”

I should add I have a serious history of sexual trauma. So even hearing the words “assault” being referred to my boyfriend whom I had trusted so much severely triggered me. And then to be coupled with “but don’t worry about it” really through me for a loop. Was I assaulted? Or should I not worry about it?

I forgot about it for about 8 months and one day, I remembered the trigger word “assault.” It helped to try to remember what happened and replay the details in my mind to reassure me it wasn’t assault. Though at this point.. I can’t remember much of anything at all!

From then on, my ocd brain has replayed the scenario constantly sometimes all day every day making the details even more convoluted. I’ve spoken to my boyfriend multiple times and he has always reassured me he truly thought I was just playing around when I originally said I was tired because we had played like that before. He has held me with tears flowing down his cheeks saying he truly would never want to do anything to hurt me.

I believe him. But my ocd won’t let me be. It constantly has me googling images of different expressions online to find an expression similar to his surprised and offended look to ensure it was not a threatening look.

I am becoming increasingly worried my ocd is going to end my relationship with this man I love so much. I crave the certainty that it wasn’t an assault and I can never truly get that and that’s what makes it so hard.

Please help.