Now you know what you are dealing with, its not such a shock. You say you live alone? OK, bring your shower towel and spare towels down low if you have them up high. Reaching above your head after the op is just about impossible until fully healed. Hanging out washing is the same. Have you a dryer or a lower clothes horse line you can use? Have your sheets fresh before the op and you won't have to worry about changing them straight away.
Think about the practical side of no boobs. NEVER have to have a mastectomy ever again. No heat rash under sagging boobs in summer. You might want a few button up the front blouses as its easier than pulling over your head for a start.
I have one boob missing and honestly no one ever looks at my chest even though I never wear a bra at all any more. Even nurses interviewing me for successive hospital visits have not noticed I have a missing boob when they have asked am I wearing a bra or not.
Don't worry too much about being overweight. It just means you have to be a bit more careful the older you get about putting more on. Smaller portions and even skipping a meal is ok to do. I just have to look at food for the weight to go on lol.
We might be a bit plain in the looks dept but we can still be clean put a smile on. Hugz <3