Since you're both practicing psychotherapists, maybe you can appreciate this trope:

Nobody sets out to become a therapist if they don't already have issues themselves that they are looking to gain insight into!

Even if you don't appreciate the trope, it doesn't just come out of nowhere. Several studies have shown that a large percentage of psychologists, for example, are indeed suffering from mental disorders themselves, and other studies have shown the importance of therapy for therapists.

I can kind of understand why you probably feel tempted to expect more from your girlfriend given your shared line of work, but no amount of studying the human psyche or practicing related subjects is going to render someone immune from personal trauma, poor communications skills and whatever else.

You're asking questions you basically already know the answer to in the hopes of a 'Hail Mary' because you love her and don't want to part ways with her, but you already know you can't possibly effectively meet the needs of someone who just isn't able to identify their needs or communicate them.