
I'm totally cool with couples doing swapping when all parties consent to it. However, the wife was pretty much forced into it and did not entirely give full consent. I would agree with other commenters that their marital problems are far more than their sex life. The should seek counseling and sex therapy to work out their issues and try to salvage their relationship. But the husband pretty much "checked out" of the relationship long before the swapping. He was looking for a way out. The husband needed to be honest with himself that the love he once had for his wife was no longer romantic love but platonic love. Also, why was the wife so obsessed with having another baby? They both can tell their married life wasn't going great. Not a great time to bring in another kid.

Its more like a familial love than platonic love, he stay not because he love her but he is use to seeing her everyday, like a daily routine a thing/person in your life you are quite familiar, the sex might not be good or there is no love in the relationship but the husband didnt want to lose that comfort and the thrill that he experienced, why let go and start again when you can just do both, disgusting right?
Hahaha this manga is a hot mess.