i am in your wife's position and dread the fact i know that illnesses can change peoples personalities and relationships. i rely on my husband for a lot of things, although not as much as your wife by the sounds of it. e and my husband have talked about the kind of situation you are describing. I have asked him that if he ever feels like he is in the position to want an affair then he be very descreet so i don't find out - as long as he dosent fall in love or leave me!!!!. My philosphy is what i dont know cant hurt me. I realise in reality that scenario is unrealistic, so just hope it never happens! However, i feel i have given him tacit permission to have an affair if he needs to.
It is an awful situation for both partners because i cant help what is happening to me and he cant help resent the fact it's changing me! Mostly i deal with it by desperately trying not to make him my carer.
I cant belive it, i'm actually crying writing this because it seems so bloody unfair for him