ya i agree totally its part of aloving intimate relationship its just frienship without

I think this answer the question: Yes, provided your sex-drive has gone and/or are physically unable to have sex anymore. Or when external circumstances make it impossible.

Bear in mind that these couples DID have sex in the past, when they were first together and throughout their lives. They probably wouldn't have made it to the stage where sex was impossible if they hadn't had a fully functional relationship before that time.
Fully functional includes sex and intimacy. Sex, intimacy, making love, are big big part of the bonding between a man and a woman.