Yes, it sucks. It doesn't have to keep you from having a relationship or relationships, though.
Anecdotal, but I've been fighting mental health stuff for over two decades at this point. I thought for a long time I couldn't have a healthy relationship. Some days, some moments I still do. I'm thankful, very thankful that my good and/or neutral days far outnumber the bad days. For me, it took a lot of work. Therapists, psychologists, multiple medications, and a lot of time. None of the medication I was ever on helped me, so I had to figure out something else.
I've lived more years than I ever thought I would see, honestly. I thought I would have killed myself a decade or so ago. I won't even try to say this applies to everyone, because of course it doesn't, but I think for some, many even, it eventually gets better. Not necessarily because the mental illness goes away, but because people find what works for them. The right medication, the right + healthy coping mechanisms, and so on.
I hope it gets better for you soon