Mental illness?

Laura.
I need someone's advice I think my parent suffers from mental illness (not diagnosed) and I've wondered for years... I don't know what to do, It's isolated me from living my own life I'm 27 and help financially because she won't get a better job.... She has no friends and doesn't go out, she has weird mood swings and she gets mad at me for no reason and I have no idea what I did. I've become depressed because if I leave or do something without her or try to move out she acts like I'm killing her. I needed to vent I don't know what to do, I feel so alone and embarrassed to tell anyone about it in my extended family or friends... Does anyone have advice or resources to help ??