Hello Ross, I'm sorry to hear you are feeling so much heartache. I do understand that how clear something is doesn't necessarily mean it is easy to process and cope with. I am also new here, and have seen several members refer to having or seeking knowledge about our past lives as "opening the box", and what an accurate image that can be - regardless of whether we sought the information or it came to us unbidden.
Not sure I have an answer to your question unfortunately, however I can empathise after a fashion. I have met someone whom I believe was my child in a past life, and they have inexplicably vanished from my life which is very painful, as I have no idea whether or not they are all right. Last time I saw them, they were in a relationship that had some toxic moments and it has tortured me worrying about them given our past life connection, even more so than it would have done if I was only ever a friend.
I am not sure if they remember their past life or not as they never really admitted to it. However, one of the last things they said to me with an uncharacteristic expression of anger was, "I don't need you to take care of me any more." It almost hit me in the face, it was so blunt and completely out of the blue as they loved meeting up before that. They still smiled at me and were genuinely kind to me briefly after they had said it, so they might have been struggling with the energy of the previous connection without realising it. However, they have now gone and I am not filled with confidence that they will ever come back. I think they are my twin flame, and there is supposed to be a reunion at some time, but time will tell what that consists of. It may not necessarily be romance or being together.
This hurts a great deal for me, and I'm sorry that you are also suffering from your past love. The only possible sense I can make out of any of it is that perhaps we have gentle lessons to learn about letting go? My twin flame has apparently arrived to teach the lessons required to clear all past fears and blockages... which they seem to be doing by leaving me so we can each get on with our soul work. Recently, I had a past life reading done, and the lady concerned told me that at some point in one of my past lives I had had to leave something or someone behind and that left a mark on me that is still palpable, so now I have trouble doing so as I am fearful of ever feeling that pain again. It's true - situations and people have always been hard for me to leave, even if they were detrimental to my life.
Maybe you are being shown a similar path? I could be wrong, but would like to think that things like this happen for a constructive reason such as that if we feel pain, it's because something is being called to our attention about ourselves in this life, that hasn't been dealt with, rather than it being all about the other person's absence. I also asked a similar question to yours at the end of the 'My Past Life Child?' thread, so it's not at all like I have all of the answers, and I do struggle too.
I know this must be so hard, but I hope that you do find a way through this, somehow, eventually. Sending you kind thoughts.