Sugar's advice is to stay with him and try and make it work. All the commenters agree, except one, who is also disabled:
"I am disabled as well and this is very very very bad advice. We don’t have to put up with unhappiness such as the writer describes due to circumstance we find ourselves in. You basically tell her she’s weak and she has no CHOICE but to make the most of a situation that is not making either partner remotely happy."
I wish the above commenter was right, but I don't know. That's why I haven't left a comment of my own.