Romantic Relationships cause EUPD

I'm only triggered by romantic relationships it seems.

Does anyone else feels this way?

I was so stable in my life after my initial breakdown, which occurred after the break up of my 10 year partnership.

I was diagnosed with EUPD but after about 2/3 months later, I had rebuilt my life and over the next year, I became the most stable person I'd ever been. And the happiest person I'd ever been in my life. I was 29.

Then I met someone who I fell for and after a few months together, things started to fall apart. And the past 18 months have been torrid.

I don't see a way out. Stay together and there're emotional breakdowns between us, break up and I lose control and the emotional intensity is too high. Anyone else found this situation? I don't seem to have a problem in any other areas of my life, other than romantically. Though other areas are affected when I'm in amongst this turmoil.

You're describing more or less what I've lived so far, close romantic relationships where I can't just "get out" when I want to because either the other person or myself won't let me are usually the trigger.
I've found so much peace now that I've dedicated myself to be more self-sufficient and think about myself first (a bit selfish but it gets the job done!)
My first 2-3 relationships were absolute hell, and the last one was precisely what you described with breaking up causing me to only want to cling harder and staying with them basically triggered episodes of dissociative rage at worst (I don't know what to call them) in the end I had to make her absolutely despise me to be able to free myself because otherwise I would just keep coming back

What I've learned from all these experiences is that stress will absolutely make things worse, things like working an entirely new job with no previous experience certainly made my bad side come out a lot more often, communication is KEY, letting them know how you feel and how it isn't their fault (or your fault either) is very important as well! It's probably the only reason why my current open poly relationship works at all, I take breaks when under stress and always communicate things, I hope you can find peace in the things you do and the way you relate to people, its possible, jut take a bit of practice and knowing yourself (which you seem to already started to do, great!)