However she broke, she went out on a night out and was sexually assaulted... she didn't tell me till months after she came home...
Also worth mentioning she admitted to sleeping with someone after being assaulted...
It's understandable that emotionally she's all over the map. People with BPD (pwBPD) are emotionally all over the map anyway, but this would be a big trauma.
However I will write a few comments, hopefully you'll accept them as objective observations, they're intended with the best of intentions.
First, you don't conclusively know what actually happened since you weren't there. PwBPD have been known to wildly exaggerate and obfuscate the full truth. Hopefully she brought back with her the police report or witness statements and that would support what happened. Even if it did happen as she claimed, you may never know whether her actions and choices placed her at risk in such a bad situation.
You wrote that she separately slept with someone afterward while she was away, and is currently with a new partner. It is your decision whether that is a deal breaker for you. If you were married (a typical obligated relationship) this would be a valid basis to end the relationship, even without blaming the end on any specific issues.
Skip to a couple of weeks ago... I leave her on a night out... she stays with someone... and proceeds to tell me she is moving in with this person and taking the kids with her... because of financial reasons... and that the house we live in triggers her...
During the two weeks I have reassured her that I wouldn't abandon her...
And all you did was be apart for one night? You won't abandon her but she's abandoned you for another guy, for now?
Sounds like she has you quietly simmering on the back burner while she has other guys cooking on the front burner, that's a stove/cooking analogy. Can you realistically see a lasting future with her?