Sorry to hear this bro. Same experience with me after 6 years as well.

IMO avoid moving in until you're married. It puts such a strain on the relationship. Also I think you're doing a good job giving her space, but also showing her you still care.

She is having some extreme crap going down and I think she is really confused. It may not even be directly related to you, just somewhat of a catalyst....

She's in a rut and thought a major change might help, but removing her main stability (being you) she sees it isn't as glorious as she may have thought. I hope it all works out man, stay positive either way.