I mean if you think there's a problem there's obviously a problem.

I would take that statement to mean "I care about you and I want to keep our relationship.... but don't make me fix it." Perhaps she knows something is wrong but it could be that things are too intense and entangled now to decide what. Which is perhaps a feeling you share?

If you have an issue with each other, it's going to surface (unless she is the kind of person who can just hold in feelings forever). How would it be to just keep going back for a few sessions and pretending nothing is wrong, and talking about other life stuff? I think that's the test of it. Isn't there a thing like that in DBT? Like deciding if the relationship is more important, or what you need? (I'm not an expert on DBT)