The main point is that most of the problems with modern relationships in some way or another relate to ‘emergency mating behaviour’ when we’re not in fact in an emergency; we’re being bombarded with so much high-stress imagery (particularly but not exclusively war imagery) that modern relationships are prone to unnaturally high levels of anxiety that leads to break-ups and abuse.

If people were less stressed, less subconsciously worried that their partner might vanish overnight, any night, they wouldn’t become jealous, start rows, cheat, etc with nearly the regularity that they do. Its as if we’re trying to maintain relationships while looking out for the next bullet because that’s what we see all the time in the media; war, war, war changes the way people behave about sex, sex, sex.