There does seem to be a lot of people (males and females) looking for an excuse to escape a relationship. Honestly I believe many of these relationships are already failed because both parties have essentially quit but are 'going through the motions' and when the 'motions' change then it becomes easier to quit than adapt, just like it was easier to stay together than split.

This behavior just reminds me of the concept of a philosophical zombie. They seem to make the choice not through conscious thought but through unconscious programming.