Here I go Again by Jen Lancaster

Sometimes karma can be a real bitch -- especially when you're a total bitch to those around you when you're in high school. Lissy Ryder was the queen of everything back then, and now she's riding (if you can ride a downward slide) on the results. She's lost pretty much everything she wanted (I can't say cared about, because all she cared about was herself). Instead of being the darling of her high school reunion she's the demon. Life isn't pretty.

Think about it. They say, "paybacks are hell." But what if you could go back and undo your wrongs, to avoid the damage you've done others, and restore the world to some sort of better place? Remember though, valuable lessons taught by Buddha and Marty McFly. You can't change the past without changing the future; all those butterfly wings, pond ripples, and missed first kisses. Lissy learns the hard way, and at 37, actually begins to grow up.

I picked this up after seeing reviews on Goodreads, librarything, and The BookReporter. The reviews were basically right. It's kinda fun when chic lit makes you think and makes you laugh as well.