On Unlikeable Characters

As I was (voraciously) reading my copy of The Party by Elizabeth day (provided as part of my Little Brown & Company ambassador program), I couldn’t help but think about the effect of an unlikable character on a narrative. Martin, the main character, is morally ambiguous at best. But this information is delivered like breadcrumbs left in a trail for the reader to piece him together, as well as the mystery of why the story begins with his police interrogation.
Unlikeable characters seem to be an obstacle for many readers and, for the most part, I would include myself in this assessment. At least I thought so. But there are exceptions, including the aforementioned book, as well as the ultimate example that leaps to mind: Gone Girl (which is always excellent food for thought). Funny enough, The Party is the first book the TRULY reminded me of reading Gone Girl. Something sinister is afoot from the beginning, and the tension builds as you learn more about the past and all of these ostensibly irredeemable characters. Additionally, part of the story is told through flashbacks, police investigation, and the diary entries of Martin's wife. And, like Gone Girl, I devoured it! It was really compelling stuff. 
Of course it's had me thinking about what makes these characters readable for me, and other 'unlikeable' characters infuriating?
The first realization I had is that they are thrillers and I tend not to put myself in the shoes of someone who is, for lack of a better word, crazy. So the suspension of disbelief is built in: this is totally not who I am, nor anyone I know, and it is FASCINATING. Clearly Amy Elliot-Dunne is a unique character and I can't identify with her motivations, but I CAN furiously turn the pages to see what she might do next. 
Second, thrillers have plot and a sense of urgency. Many of the books that center around a character I did not care for seem to be more of a sociological study than a story - such as Hausfrau or Rich and Pretty. I have a hard time with this type of book as it is, so not having an emotional investment ruins the reading experience. 
Lastly, the characters that inevitably ruin a book for me are the kind that make repeated stupid mistakes and never learn from said blunders. Yes, we all make mistakes and the plot of a great story usually revolves around one. Yet either you can identify with choice the character makes (however stupid), or he is penalized, or learns from his transgressions. In the party, Martin is a very unlikable guy, but it is easy to see why he does the misguided things he does, which in the end, leads him down a dark path that is revealed by inches with searing commentary on current culture, including class and sexism.
OK, obviously I enjoyed The Party. Any recommendations for other despicable, yet fascinating characters? Would love to hear more thoughts on on this pervasive trend in books!