Partner/meta breakup

My partner is going through a breakup with one partner and possibly also with another. They are devastated and I am too. My metas are a deeply important part of my family. I have a hard time with change even when it's good and this change makes me really really sad, especially in conjunction with watching my partner dealing with it all.

Any advice for this? I care a lot for all parties, I obviously am not going to be getting in the middle of any of it, I'm also not going to be able to (nor do I want to) be all the way separate from it because our lives are all quite entangled. This is my first serious experience with a partner/meta breakup. Looking mainly for advice on how to work through with my own sad feelings and experiences with these changes.