Now the decision is reluctantly made regarding need for a mastectomy, have you considered reconstruction?
It is often good to plan this as part of initial surgery.
This link gives brief overviews
https://www.bcna.org.au/understanding-breast-cancer/treatment/breast-reconstruction/More detail here
https://www.reclaimyourcurves.org.au/And we also have a breast reconstruction group you can join.
https://onlinenetwork.bcna.org.au/group/1-choosing-breast-reconstructionReal women, real shared stories and also real pics.
We all get the heartache. I was devastated also. But once i settled on the plan I just wanted the cancer gone. I will always miss my breasts but I've never regretted my decision.