Help pls.. ocd???

I’m gonna try to make this make sense, and any support or advice would be great. I have a beautiful girlfriend, who I’ve been dating off and on for a year. We were really rocky but got our shit figured out 4 months ago and have been strong since. I truly love this girl more than I’ve loved anyone. And I know based off the sheer amount of ocd that has come up on our relationship, that she means a lot to me. Me and her were in a friend group in 2022 and we never liked each other. However she had a sexual relationship with one of my old friends. Fast forward to now I haven’t talked to him in a long time and I don’t see it as an issue. However… I keep having this vivid flashback to him touching her some kinda way in 2022. I can’t remember exactly what happened or the details but it’s running through my head. I guess this is retroactive jealousy but it’s really almost hurting my feelings. I wish it would stop but I know ocd doesn’t work that way. I just wanna be happy with my girl and not upset at her past experiences

For some time i was obsessing over relationship with my girlfriend. For a long time we we're each other's best friends and we only had each other. Recently she made a good friend in work and im obviously really happy for her because she deserves to be loved by more people than me. But i started to feel really jealous. I never thought she can cheat on me i just have really low self esteem and i started to obsess over if she is still in love with me or if she is still attracted to me bc she sometimes would be more interested to spend time with that friend and not me. We talked about it a lot and i tried my best to not be jealous and give her space but i felt how she's distancing from me. At some point she stopped showing me her love in any way. She stopped hugging me and kissing me and she kinda stop telling me she loves me. She only responded "me too" when i told her i love her. I talked about it with her few times and she always said she understands and that she's tired and don't really need physical touch etc. But i was still worrying bc i just knew something is off. She really was acting different. And then few days ago she told me she's actually tired not because of job but me. She feels irritated by me and she don't know why and that she actually thought about breaking up with me and she don't know what to do because she's confused about her own feelings. She said she thinks she still loves me but it's hard for her to see a difference between friendship and love and that she feels tired of concept of dating someone. She said we should wait and see bc she thinks she still loves me but i don't know if that's honest. I don't know what to do anymore im crying all the time every day since that conversation we had. I feel like my worst nightmare just came true and now it's real and not only a though in my head. I can't do anything and i feel like it's the end of the world. We're living together and i don't want to go back to my parents but that's not the worst thing. I just love her so much and i can't hande thought of loosing her. My ocd made me question every single thing about me but somehow i never questioned my love for her so that's why I'm so emotional about it. I don't want to lose her. I don't know what to do i just want to be loved but I don't want anyone else. I don't know what to do im so scared. I want to die every time i look at her with love in my heart and i know she doesn't think about me like that anymore.

Not directly OCD related, but: The therapist I will be talking to is not yet my official therapist and to keep a long story as short as possible: I’m from Germany, you usually get 1-2 sessions without “signing a contract” to see if you get along, I haven’t signed yet because I honestly want a different therapist but I also don’t want to wait 6 months and this will already be my 4th session with her. This time, me and my best friend will both attend at the same time since we’ve had ongoing and reoccurring issues for the past 6 months in our friendship, including confusing romantic feelings on my behalf and an overall misunderstanding and misinterpretation of each others feelings towards each other. We both recently graduated and she already knows what university she will be attending (somewhat pretty far away from mine) and even if I wanted to I most likely can’t live near her or attend the same uni. I don’t know how to explain this, but I have been grieving part of our friendship for the past year and the first time I felt like something was off was about 1 1/2 years ago. We haven’t been friends for that long (about 2 1/2 years) but we became very close friends very quickly and I do not want to lose her. However, I do feel like she has changed. Not personality wise but in her attitude towards emotions and friendship? We used to talk so much more and everything felt happier in the beginning as it does now. Obviously our friendship has had its hardships in the last 6 months (she liked/likes(?) a boy, I liked/like(?) her, she used to like be but only in the beginning of our friendship) but I miss our conversations and picknicks and just hanging out with her like normal. We also hat a time in which we didn’t talk to each other for almost 2 months and NOTHING about this made anything easier. I’m genuinely trying to detach myself from her like she did with me but nothing works. Last week we had our high school grad ceremony and we danced and when I held her hands to guide her through the people dancing, I felt those stupid butterflies again and I genuinely don’t know what to do. Sometimes I think I wouldn’t even befriend now her if we were strangers, but we made so many memories and I hate change and graduating, moving away from ALL of my friends and losing the best friend I ever had is too much for me. I get so jealous thinking about how she is going to met new friends at uni and finding a partner and forgetting about me. And I don’t know how to say any of this tomorrow because my therapist honestly doesn’t seem to care about anything I say and neither does my friend. Everytime I say that I feel like there is an issue we need to solve or talk about she just shakes it off. I feel helpless.