You just said it. You CAN'T change anyone, but you can change the way you interact with her.
I noticed you recently gave me an advice in another thread, and i appreciate it. But well, from what i can see, the situation is a little bit ambiguous, since it seems like your mother is either angry or jeallous. What i can say is that you could ask her what bothers her. You said that she is still caring. Maybe she was scared at first thinking she could lose one of the few people she could live with (you said she doesn't have many friends right?) when you started studying and latter married, and latter angry because you made your own life.

Well, it's the way i can see things.
My only advice is to talk to her in the nicest way possible asking her what troubles her mind and how can you help her.
I hope you can get this work out. good luck!