I am sorry you hurt.
Sounds like poly hell.
Perhaps reading that together could help you guys salvage / learn from it and set the polyship back on course.
Or if you are done, and feel like you don't want to be in polyship with GF or DH any more... could shelve it for a time. (You pick the time -- a day, week, only you know how much you have to think through. ) If you are still done with them in that time? You are still done with them.
But could not make major life changing choices while in an high emotional state. YKWIM? Could take a time out to cool off and even if you come to the same conclusion that you want to break up with both of them -- you arrive at it from a cooler head kind of place free of emotional roller coaster wackies. And if not totally free -- at least "lower in volume" so you can form your next steps.
I can imagine it must feel very hard. Hang in there.