As a mother I know I would be devastated if my daughter were to leave me, something I would never be able to come back from. However even though I'd be heart broken I would eventually come to the understanding she did what she did because of her pain and her struggle only she fully knew and I would eventually accept and appreciate she was no longer hurting. The grieving would never end though, I know that, but we mothers can't be selfish with our children and we would never stop loving our babies no matter what until the day we are done here. Try talking to your mom, maybe she'll understand, she may never be "okay" with it or supportive per se but if the day were to come she may be better prepared to cope with the aftermath because of the open communication you had beforehand. Sending you lots of love and hugs, I'm so sorry you are suffering my dear.