The Upside of Irrationality is a boring book.
It's the sequel to Predictably Irrational which I don't think helps you understand dating as much as it helps you understand that people are prone to irrational behavior which you'll see in dating time and again.
There is however one good chapter in The Upside Of Irrationality on of all things online dating. The chapter contends that online dating is a market in failure. There are a series of experiments that back up this idea in the chapter but much of it is focused on how online dating doesn't simulate a real date because you are essentially window shopping based on pictures and a few descriptions that anyone with half a brain could fake.
There's also some good stuff on ugly people and how they rationalize not being able to get the mates they really desire.
It's probably not worth reading the whole book, but if you have 30-45 minutes free to read the chapter it's pretty interesting.