Sorry to hear about your mother issues. She sounds a lot like my mother. "Don't you ever think about anyone else?" or "Think about what you are doing to me!" You may want to read a book called "Toxic Parents" by Susan Forward. It was very eye-opening for me. You mother sounds narcissistic. I know we tend to think of narcissists as vain, but they are much more than that. Google "narcissistic mother" and check out that book. It may help.
In the mean time, stay the course. People who try to detract you are only doing it for themselves and not for you. If you had a healthy relationship with your mother, she would be more understanding--unless she's just working through the five stages of grief. Not sure how long it's been since you've come out to her but based on what you've said it sounds like she is just focused on herself.
Jane.