The Between Boyfriends Book: A Collection of Cautiously Hopeful Essays by Cindy Chupack. Cindy Chupack was a writer and producer for Sex and the City, and it definitely feels good to have something funny in my book pile at the moment.
Don't Call That Man! by Rhonda Findling, M.A. Not surprisingly, this one kind of got scrapped.
He's Just Not That Into You: The No-Excuses Truth to Understanding Guys by Greg Behrendt and Liz Tuccillo. I've mostly just been reading the "He's Just Not That Into You If He's Married (and Other Insane Variations of Being Unavailable)" chapter.
It's Called a Breakup Because It's Broken: The Smart Girl's Break-Up Buddy by Greg Behrendt and Amiira Ruotola-Behrendt. It saved my ass during the unixd0rk breakup, but it feels a little too angry for me right now.
It's Easier Than You Think: The Buddhist Way to Happiness by Sylvia Boorstein. Recommended by planetjupiter, but I'm not really feeling it. I think now is not the time for me to be reading about religion.
Monica's Story by Andrew Morton. The biography of the most famous "other woman" ever, Monica Lewinsky.
Will He Really Leave Her for Me?: Understanding Your Situation, Making Decisions for Your Happiness by Rona B. Subotnik. A psychological overview of all parties involved, and the likely chain of events.
What else am I missing?