The thing that concerns me is that you see this as a waste. I started out as a political science major, before I transferred and changed my major to an English degree. Since then, I've tacked on an art history double major (and transferred again, but that's a separate issue). I don't see my time as a poli sci major as a waste because it made me realize what I really wanted to do. My situation is probably a little different because I also transferred to a cheaper school, but I don't regret those years I spent at a private school, even if they were expensive. I made some very good friends, but more importantly, I learned a lot about myself. Both academically and personally. All of the skills your girlfriend is learning from any of her classes are helping her build her future. Maybe you need to try to think less about the negatives and more about the positives of the situation.

Honestly, maybe she should double major. Mental health is a big political issue right now. She could also look into the option of majoring/minoring.