Just like to echo what Leed said about therapy, it's something that has helped many of us (I'm happy to say I'm one). Therapists are trained to help us deal with situations we have trouble with and there should be no shame in consulting one - having said that I was originally reluctant myself (I think I was scared, scared that it meant I was mad, that I wasn't coping - all nonsense of course). It took a friend to persuade me to seek therapy, it was one of the best things I ever did. A therapist is neutral, they won't blame you or confuse things further with their own issues (like even the most loving well meaning family can unintentionally do), they can also help you with communication issues.

In the meantime one little gem of advice my therapist gave me which I find useful and you may possibly too - separate your family members 'stuff' from yours. You can't change how your mother (or anyone else) is but what you can change is your reaction to her, you can still love her but let the line be drawn, this is your life and your decision, it's very likely taking control of it will be a good step towards feeling better.

Best of luck whatever you decide to do.