Your mom may need to be educated. Transgender issues have gotten a lot of visibility lately, but not everyone is tuned in, and some of the media coverage is still atrocious.
I'd suggest making sure she knows:
* You did not choose to be transgender. It's something that you were wired with from birth.
* There is no cure for transgender. No one has ever found a way to make it go away.
* Transgender is serious. Depression, anxiety, and even suicide are common among transgender people who ignore their condition.
* The only treatment that has been proven to work is to transition to live as your true gender.
Good luck Rhys. We're here if you need us.