I had a breast reduction surgery when I was 23.
I was a 32H or 34GG, back then. I had terrible neck strain and back aches as well and bloody notches in my shoulders where the bra straps crossed.
Ditto ALL the advice about 1) a proper bra fitting and 2) a supportive mattress and 3) stop using pain killers and 4) she must wear a sports bra or similar to sleep in, to support those girls while she rolls over.
I would highly recommend your mother mind her own business. Stop asking for her input or providing any updates to your mom. Her healthy diet input is wrong and inappropriate and even mean spirited. I am shocked your mother is this involved in the first place, but it's clear there are some long standing boundary issues with her.
Honestly, my breast reduction surgery was between me and my surgeon and no one else. But I wanted to have the surgery, not my mom.
Have you taken your daughter to an actual surgeon yet so that the surgeon can discuss the pros/cons and procedures and she can ask any questions and they together can decide???
Honestly, a surgery like this is simply not up to you.
I do not regret my breast reduction surgery at all. One thing that helped me make up my mind was talking to a girlfriend who had the surgery and was very pleased with the results.
I had one big fear and that is I wanted to breastfeed my babies one day. So the surgeon was very careful not to cut any lactiferous ducts.