This comment from a reader over on Chump Lady pretty much sums up how ridiculous the argument, “He/she deserves to be happy!” is:
Weird, isn’t it, that in this view everybody except the betrayed partner and the kids “deserves to be happy.” Cheater gets happiness. AP partner gets happiness. Their families, friends, colleagues, and eventual wedding planner get to be happy about their happiness.
Actual spouse and kids? Weirdly, the happiness train does not stop there. Of course, the kids can ride every few weeks, if the cheater has time, if the AP doesn’t object, if the betrayed spouse drives them to the station and pays for the tickets, and if they are not old enough absolutely to reject the whole idea of playing along with the rules of bizzaro world.
And when the chump finally gets it, escapes from that train wreck, and goes totally no contact with cheater and cheater’s weird world? Why, there’s the evidence that chump is anti-happiness, which is considered overwhelming evidence of why cheater needed to cheat.
Hmmm. Pretty brutal, this “happiness” thing. I’ll pass.
When your happiness is achieved at the expense of others you aren’t pursuing your own happiness. You’re being a selfish, entitled, spoiled nitwit.