You have done much for the family and if you can not give to your friend with cancer at this point it is ok. I believe God puts ppl in our lives when we need them. For the moment you can not be there and it is ok.
I could not be there for my sister that had breast cancer 5 years ago but she tells me of a lady who was able to be there for her at the time in the way that she needed. I wish it could have been me but at the time it was not possible.
Last week I was able to nurture my mother who is 80 with alzhiemers. I was able to put aside past at the time with help from sisters. I litterally had to hold and rock my mother as a child to reassure her she is safe. I never dreamed I would ever have to do that for her but it was possible and with sisters doing what they could in the way they could helped even more. So I say yes, 86 year old can be nurtured expecially in community of nurturing ppl.
Larks