Wow. Are we the same person?

I can relate to 98% of everything you've said. You're not alone, that's for sure.
It's been a long 3 years this has.
On/off/on/off
Everything I read about BPD 2 years ago all ended up being true in my case, after each recycle I became less and less important to her and we have reached the point where she just doesn't care at all now.
I'm there, too. Mine was 4 years of the chaos and the push/pull and the constant recycling - even these last couple of days she's been begging for another chance, but it's definitely at the point where her behavior makes it very clear just how little she cares.
I have sacrificed myself at the alter for far too long, and it's cost me so much.
Same. I lost so much that it felt like I ended up tossed from the Garden of Eden into a desolate wasteland. It's ridiculous how severe the damage is when we survey it at the end, isn't it?
It will be some time, I think, before I have my strong sense of self - and self-worth - back to where I feel like I am
me.
In truth I don't actually blame her anymore, I think my compulsion to repeat the cycle has been what's kept it going this last 6 months.
Just not being able to shake the feeling that this was "supposed to work out"
Yes, that compulsion is a very real thing. But, remember, it is a learned behavior straight from the dynamics that her disorder dictated for you for all those years. You
can break the compulsion. I'm struggling with it, too, but I'm just so exhausted anymore that even if I wanted to recycle with her, yet again, I just really don't have the energy to do it. It is a good place from which to start the NC and the healing.
I 100% was convinced - and I mean
convinced - that she and I had a real shot at what everyone hopes they will have someday. I'm slowly coming to terms with the reality that it was never possible - it only felt that way because of how exquisitely perfect the ideation phase made everything seem.
But, over time, the devaluation phase became the norm, and when I stepped back to look at how much time over the 4 years I spent being devalued vs. how much I spent being adored... .it became very obvious that I'd spent 80% of it in misery trying to regain the 20% that had been so nice. I didn't know anything about BPD at the time, but if I had I would have walked away years ago before the habitual recycling began.
If the same is true for you, then I hope it brings you the same comfort it brings to me. You are stronger than you know. You can make it through this. If you couldn't, you wouldn't have hung on through so much pain and suffering, right?
But truth is I really do have more than my fair share of own issues that I need to work on. I've been like a dog chasing a car to be honest, I wouldn't know what to do if I caught it.
It was my choice to ignore all advice and think I knew best. My choice to keep going back.
Ah. Yes, we all have our own fair share, don't we? Especially here on these boards, I think. I know my relationship with my BPDex definitely opened my eyes to things I never even knew could be an issue for me - and that I have much more therapy to go through to find better ways to manage and cope.
It's sad that what was once a strong bond now means nothing but it's my time to move on and try and sort my mess of a life out.
It isn't just sad. It's downright tragic, if you ask me. It is heartbreaking that what our BPD partners want so badly - to love and be loved - is the one thing they just cannot allow themselves to have. And the strength of whatever allowed you to weather through the ups and downs just breaks down over the repeated use and abuse. It's a devastating experience, and I am so sorry you've gone through it.
But I am deeply encouraged by your closing line. I, too, am in that very same place. And I believe we can make it through as better, stronger, and healthier people.