Celebrities hook up all the time…but this year there have been quite a few flings that left us flung.

Avril Lavigne and Chad Kroeger pulled off the ultimate surprise when they revealed that they were not only in a relationship…but engaged!
 
We didn’t know what to think when we learnt Mary-Kate Olsen and Nicolas Sarkozy were getting cozy.

And how about Bar Refaeli and Shaun White?  We thought for sure the rumors of them dating were just rumors until they posted a pic of them posing with the Phelps family at the London Olympic Games.

Check out these couples and more!