I believe "god" made some of us with "some reassembly required"
I hope the surgery will go well and that you will heal swiftly and well. I hope your mother will come around to the notion that this is necessary gender affirming surgery. "god" made me with weak eyes and I nearly went blind as a premature baby if not for modern medicine. One can argue that "god" has a calling for each person and for some, that calling is to be surgeons performing gender affirming surgery.
Maybe introduce her to some trans affirming theology
I have been recommended these 2 personal memoirs:
1)
This Is My Body: Hearing the theology of transgender Christians by Christina Beardsley
2)
My Name is Brett: Truths from a Trans Christian by Brett Ray