If a couple or significant other have been together for lets say 20 or 30 years, and one of them losses interest in Sex, but both of them love each other more then ever, but one still needs sex, or is more sexual, does it matter if he or she looks for sex elsewhere to fulfill their needs, but in his or her mind, their love is forever. Neither one of them are looking to have a relationship with another person, just having to satisfy his or hers desires. What are your thoughts, and put yourself in their situation.
As long as it's talked about and all above table...
It matters. It matters a great deal. If the problem gets discussed and both people in the marriage agree that it's permissible for one of them to seek sex outside the marriage then go for it. If both people in the marriage do not agree to this but one of them seek sex outside the marriage anyway, then that's cheating and betrayal. I recommend that the party feeling he or she needs sex present his/her case, discuss it, and decide how to proceed from that point. If the partner needing sex does not get consent to seek it elsewhere from the other partner, then sexy needs to decide whether to accept those terms or whether getting the sex is worth ending the marriage.
If one partner isn't having their needs meet then they have every right to get those needs filled elsewhere but need to be totally honest about it. People change mentally and physically as we get older and those are things that need to be dealt with.
I'd be crushed if I failed to meet my partners needs and didn't allow her to get them fulfilled elsewhere. I don't own her or her orgasms.
This is why communication and honesty matter so much. If one spouse has a low sex drive but is made to understand that sex matters enough to their partner that they are considering looking for it outside the marriage, then this could be a game changer on several levels.
They need to negotiate terms that are acceptable both. However, they have to keep in mind that you can't plan for everything. If you open your relationship to others 'just for sex', feelings can develop between your significant other and the new sex partner that could overshadow the first relationship. Just because someone agrees in theory, it doesn't mean they'll still agree once they experience the reality.