The Vow, by Jessica Martinez

Mo and Annie have been friends (and only friends!) for years.  For different reasons (Annie's loss of her older sister and Mo's status as an Arab living in Kentucky) they have never bonded with anyone else.  So, when Mo finds out that he is about to be deported with his family back to Jordan, it is not that much of a stretch for Annie to propose a radical solution to let him stay: the two of them will get married.

But what seems like a perfect solution at first comes with complications and problems (some anticipated, others not).  In order to make their plan work, they must convince their family and friends that they are truly in love and serious about being a married couple.  This causes understandable turmoil between the two of them and their social circles and heightens the difficulty of living together (which they now must do in order to convince the INS that their marriage is legit).  Everything gets more complicated when Annie falls in love - for real - with another boy.

There are a number of missed or underdeveloped opportunities in this book (the racial dynamics of the relationship, Annie's fears of letting others down, the differences between Mo's and Annie's expectations of the relationship, and Mo's feelings for his homeland), but much of that is because of the story's ambitions.  Martinez does a good job of setting up a plausible motivation for the faux marriage and making the set-up all seem possible.  In the end, when their plans unravel quickly, that too seemed plausible given the circumstances.  What got lost was allowing us time to truly get inside the heads of these two characters, but I suspect that would have doubled the size of this already lengthy book.