Background:

Met a girl over Christmas. She has BPD and was not long out of a breakup. Fell in love. She was everything to me, I was everything to her. We never nominatively dated but practically we did. She was very emotionally volatile but it didn't affect me at all, I was always there to shoulder the storm and I did it with a smile on my face because I loved her, and I knew underneath the defence mechanisms, she loved me.

But as she got more stable over time, she cared about me less. I realized I wasnt her everything out of choice, but out of necessity. And her feelings for me lessened. But I couldn't blame her, could I? She's mentally unwell, her brain works differently to mine, and I knew what I was getting into. But now we were asynchronous. She was still my everything, even though she felt less and less for me every day. Until she switched her sexual attraction to me off like a lightswitch. Then switched her ability to sacrifice her free time for me. Until there wasn't much left except her messaging me when she needed affection or to vent or anything.

And because I'm pathetic and revere her and adore every second I can spend with her, I didn't establish a boundary, or find something or someone else to fill the her-shaped hole in my life, I just took what I got. A call here. A few hours irl there. And the time spent away from her I began resenting her. Still do. But then I need to switch it back off again to spend time around her so she doesn't cut me off completely. I've become so dependant on her for happiness, the way she used to be dependant on me for happiness, that I can't stop. But she could. And did. And I don't know what to do.

Ethically, I think constantly about the "justice" of cutting her out of my life completely. That would show her absolutely nothing. She can live without me now. I think about trying to rekindle what we had, but it's impossible to say how that would go, and even in the best case scenario, I'd be with someone I harbour fetid rage for, and I'm worried that it would crumble again.

For now my "plan" is just to keep on going as I am, but make conscious efforts to try and expand into other good things in my life to become less reliant on her. I tried being totally without her for a while and I was far too vulnerable and needy to manage it. I hope that eventually I can have other things in my life that complete me, and I think that if I were to leave her totally I'd lack the motivation to find them. But at the same time, for as long as she's in my life I worry that I won't be able to develop feelings for someone else, even if they're far better for me. I don't know what to do.

Anyway, thanks for listening to my rant. Feedback appreciated.