I don't know what's wrong with my mother

I'm so sorry I must say such thing, being an adult and mature woman, but I can't stand my mother. She goes from up to downs, sometimes she takes her antidepressants, sometimes she tries not to. She gets terrible mood swings, when she takes her meds, she's fine the first week and then again, she's all fussy, can get angry for no reasons, makes faces, says bad words to me, tells me I don't do anything in the house(not true, I do most of the stuff AND spend quality time with my daughter AND work). She can also starts a fight over nothing, do crazy things like drink alcohol and take the car, cry and say that we are so ungrateful, that we don't love her, etc. And when she DOESN'T take her antidepressants, it all that, times 10. She doesn't work because she says she's sick but it's all in her head, she also has overweight and it makes her feel bad and sad... but the problem is that she takes it out on us. Sometimes she is so nice, generous and loyal. I really don't know what to do anymore, I want to help her but she doesn't want to help herself. I have so many other problems to worry about that sometimes I can't bare with her so I respond with anger too. How do I make her life better? What should I do?
PS I currently live with her because my apartement is only going to be ready in september so I cant just go away
PS2 she also takes sleeping pills

Thanks for the answers :)

I don't know what's wrong with my mother