I'm glad the weight is coming off but I do hope you aren't there forever. Time to get home and on with your life. I know that is in your thoughts and prayers also.
Now I understand the "hospital panties". You must be doing better, they always kept me bare butted.
Muscle. I think I did ok with muscle until my knee when south then I did lose muscle and muscle tone. I wasn't able to push around the carriages, lift stuff, all that I had been able to do before. Part of it was I was 1/2 the person I had been and didn't have the sheer weight behind the effort but part of it was muscle loss. So I am working on that now that my knee will allow it. Simple exercises every day make a difference. That will come back for you too. Right now, concentrate on getting healthy and getting home.