Fantastic story! You're so lucky to have a mother like that!
Mine has been torn up about it. I believe part of my dysphoria is due to the fact that my mother wasn't even supposed to be able to have children, so I was, in myself, a miracle of nature. Also, during my birth she had some sort of heart attack (there's a fancy medical term for it that I can't remember), and almost died. So, she did go through a lot of stress during and after her pregnancy. Not to mention the fact that she wanted a boy so badly, she cried when she found out she was having a girl.

So, I guess she got her wish, and I was only born in a female's body. And now, she's gotten used to having a daughter, I am her little girl, she just can't handle it, and is verbally lashing out every time I even mention it to anyone that she knows about. Some of the things she says are very hurtful, as she has been very close to me throughout the years. According to her, I won't have a mother once I'm 18.
But this is your story, not mine, and I'm so glad your mother is being this supportive and accepting! You cherish that ring, hun!