Struggling with self-diagnosing BPD and seeking validation in a relationship

I am almost positive I have BPD my therapist suggested I have it and after a lot of research and self doubt I believe that I have it I don't want to self diagnose because I'd feel terrible about it and feel like I am faking even though I am fine with other people doing it because you have to self diagnose before you can get a medical one my mom won't let me go to a doctor about this because she thinks BPD means I'm insane I ruin so many things because I need constant validation that I'm loved from my partner and I feel like when he's not around me I'm not good enough and that he doesn't want me I know im ruining this relationship even though he says I'm not I know I am I dont know how to stop it