try to always remember these things:
1.its not you, its 99% her
and if she gets her life together same thing applies,its 99% her decision,all you can do is to offer your love and support although it might be hard at times,dont stop loving her completely,thats all you can do the rest is up to her.
shes after all your mother,but that goes both ways,she is the mother and you are the offspring,she should take care of you not the other way around
2.youre no longer a child but a man,and in a year you can move out, just try to make the best life you can for yourself,things like this tend to make people really strong but also harsh and cynical,try to keep the strenght but not the bad stuff,go on with your life
3.if you feel really bad at times get a really sad movie/book/song and cry your eyes out, cry all you want, you will be surprised how much better you feel afterwards,its really really healthy, although it sounds like something old women would do!
if you do that maybe once or twice a year you will never develope psychoses(this is something i used to do but havent done in a while,its a really good trick im teaching you here with risk of looking like a wuss

)
be strong dude