Open Marriage

I recently confided to my best friend about my open marriage situation. I explained to him that my wife has had over a dozen lovers over the past six years and routinely sees another man for sex every Friday. He was silent for a moment, and then admitted he caught his wife cheating three years ago and, after several arguments, for the sake of the kids allowed her to continue seeing him. She convinced him, as did my wife, that it's "just sex" and there is no feeling or love whatsoever. This leaves me wondering exactly how popular this thing with open marriages really is?

— Phillip, 35