What I have learned and still struggle with sometimes is that I can only control myself--what I do, what I say. I can't take responsibility for what my partner does or FEELS. Those things belong to him.
It sounds like you want to self-medicate with marijuana. You mentioned that you avoid therapy in part out of financial concerns. However, if you have a Primary Care Physician, they can recommend medication or may know of a free counseling center.
I know you really love her...but as I have learned...you can't love someone out of mental illness and out of their problems. She has to be responsible for solving these things for herself.