Actually, I’ve noticed that the most successful marriages are those where both parties are each other’s best friend.
When a couple suddenly experience sexual problems, if they are otherwise in a close relationship, a search for a solution to whatever caused the problem will be sought without either adventuring into someone else’s bed.
Marriages based solely on “great sex” do not endure.
I quite agree, but was trying to stay on topic.
Put another way, if each spouse is willing to make an effort to keep the other happy, they will figure out a way to accommodate each other's needs.