StormEye100, hi

I'm glad you're here. I think you'll get a lot out of this forum. I know how exhausting the nitpicking and rude comments are.

With him not wanting to go to therapy is staying in this relationship pointless because it will always be a roller-coaster?
My H and I have been to marriage counseling, but he refuses individual therapy. I found validation and support, and I also learned how to respond better, and those things have helped our relationship enough that I enjoy it again. It'll always be a roller coaster, but I feel stronger now so I'm not shaken by some of it, I feel equipped to respond, and his behavior has improved. My H has BPD traits, or possibly a more mild version of BPD. Others here have had different outcomes and have decided it's too much. It will be up to you to decide what you need and what you want.
Bottom line: there is hope. It will really boil down to what you choose. And no matter what, you'll find support here.