Relationships are a two way deal. It sounds like it has been going for a while, at least several months. She has every right to put herself first if she's been in an unhappy situation for a long time.

I went through a down period a few years back, lost my gf of 5 years to it. Her leaving removed my saftey crutch and forced me to get my own shit together. Sounds like it's what the OP might need too.