Does she let you touch her at all when she goes into one of those states? Maybe you could simply hold her hand, wrap her in a blanket it if it's cold, or pet her head (that's one of my personal favorites when I'm upset). Does she respond if you say something to her? Does she say anything at all when she comes out of them? Have you tried talking to her after the fact?

I agree with Lee, I think you should see if she would be willing to find therapy. Along the lines of not being able to afford it, I recently found a place though my county that actually covers all of my expenses, so definitely look around if she's having trouble finding something she can afford. Also, the NAMI branch here has a group especially for friends and family members of consumers.

Maybe just keep reiterating how much you love her, and that no matter what is going on in her head or what has happened in her past, you will still love her, be there for her, and support her.

Good luck. You sound like a great boyfriend, very caring and supportive! Someone so many of us could use in our lives!