(((Maybs))), I'm so sorry you are struggling. This is just an awful situation you are in especially as it has all happened so quickly so it will take a while to sink in.
What you have gone through is huge and life changing, it's not just business as usual. You have been stoic through all this and you should be proud of how you have handled it all. I think you need extra support at this time, would it help to join a divorce support group?
You know that wrapping yourself up in your friend's issues is is only a temporary band aid, at some point you will have to face these changes in your life and figure out how to move forward. At the moment you and XW are taking different paths but in the future there is no saying that you might meet up again but now you need to move forward and not be stuck in separation mode.
Hugs Maybs.
Me - 47 H - 45 D-16 M - 6 years Separated - May 16
Don't leave me behind can't you see me I'm shining... (Years & Years - 'Shine')