Maybe a helpful thing to explore is what are you grieving? Something I've learned is that these relationships, while deeply manipulative and unreal, have the potential to unlock something real in yourself - unrecognised needs, narratives, wants. Detaching from the awful behaviour of the Borderline is one thing, detaching from these narratives for another.
For eg, as I've posted before, part of the hook for me was a desire to feel special, and part of the struggle for detachment is accepting that I was not special in the relationship, but a placeholder used to temporarily fill the Borderline's bottomless needs. But also, the positive qualities latched onto are real, and they are a good way to identify what I see as loveable in myself.
I’m not even actively grieving. Today was fine. Maybe I’m so far removed from any semblance of her existence, that when I see she’s still real, I go into “flight” mode. If anything, a need to be appreciated, wanted and useful? But then again I get that cup filled with work and family. I truly know if I didn’t exist a couple of people, my parents, possibly wouldn’t be alive still given their health issues, and my knowledge of healthcare given my job.
That my work service wouldn’t be as functional, have bad findings with the federal government. Everyone is replaceable but dang it if I’m not very valuable and leveraged to other hospitals across the nation. I’m “special” in that way.
With therapy, I think, given my mindset and personal goals…I’ve lived life in reverse. Most people look to build toward a home, job, cars, security, health, etc. but they usually end up starting a family and achieve those things a bit later in life.
For me, I wanted a wife and family first. Then to evolve into a full fledged adult. My ex was the only person I’ve dated in 38 years that made me feel like that was actually going to happen. Obviously not, given mirroring and all the nonsense. So maybe, the reminder of her just reminds me that I’m not where I want to be. That the main things that matter are out of reach, and the material things that were easy to achieve didn’t mean a thing as far as my personal happiness.
Plus my own personal weakness in realizing that when I see even a photo of her, that I just melt. As much as I “hate” her, I’m just like…I hope that lady is doing ok, actually taking therapy serious, off drugs, and respecting herself. She has so many good qualities that surface at times, but she’s so awful and broken. Which tricks me into thinking I could have “saved her”

so, so, so dumb of me.
The more time that goes on, it seems I’m forgetting my education on this illness. I’ll never ever reach out to her. If she does, I’ll avoid at all costs. But I’ll still be sad. I don’t want to be sad, even if it’s very rarely.
Maybe I just need a big life change, a positive one. I’m on autopilot just living what everyone considers to be a wonderful existence.