I have found that the author is probably correct. Usually, when I talk about something that is bothering me or something bad that happened to me, the person to whom I was complaining gives an example of something even worse that happened to them. It becomes a reciprocating cycle of one-downsmanship.
As hard as it is, I usually find that the only thing that gets me out of the funk of a bad day is being positive and counting my blessings. If I focus on how bad the situation is or on revenge (and I can be pretty creative when it comes to revenge), I just end up feeling worse. If I find the silver lining, it's as though a heavy stone has been lifted from my brow and I can think more clearly. This isn't about a false positivism; for this to work, I need to find something truly good in the situation or in my life and celebrate it (not ironically).
Now, demons will still try to bring those bad thoughts to mind. I find that the only way to consistently keep them back is to recognize who benefits from my misery: it isn't my kids or my friends, not my co-workers or my spouse, and it certainly isn't me. Thus the only true revenge is leaving that misery behind. I certainly don't want to support the devil that benefits from my misfortune.
Life is good and my blessings are many. My state of mind is my own to control.