There really is only one big spoiler in the movie: Who will Rae marry? Will it be Luke, Harry, or Adam?
Adam is her ex boyfriend who she broke up with at the beginning of the movie when he decided to go off on a project related to his work. And when he came back in town, there was a misunderstanding that he was dating another woman, who was really just his niece. When he came back, Rae was dating Luke and made things confusing for her, especially when the misunderstanding was cleared up.
Luke is a guy that was set up with Rae bye her minister. They hit it off pretty good early on, and Luke proposed to her. She does end up sleeping with him and leans toward marrying him until Adam comes back in the picture.
Harry is the old college buddy of Luke who shows up at his apartment to stay a while. He is basically a rich playboy who travels alot, and now claims to be in love with Rae. While Rae was confused about what or who she wants to marry, Adam or Luke, she goes on an adventure with Harry to London, and she almost slept with him, but Harry was a gentleman and wanted her to end up with Luke.
She realized in the end that Luke was her fairytale prince charming and marries him.
One a side note, Rae is a social worker and is currently a case worker for a teen girl, a girl who would like to live with Rae. Rae is fond of her, but doesn't want the child to live with her, but takes her in for a while. She does end up adopting her in the end as we hear the newly wed couple refer to her as their daughter.
Rae's best friend, who had been having an affair with a married man, ends up standing next to Adam, Rae's ex, so we assume they end up as a couple in the end.