Following the plotlines or not, it was an interesting twist on falling again for your first love. In this case, as Jane is stressing out over trying to plan her wedding, she sees her imaginary friend from childhood, all grown up. After thinking she might be imagining him again, she embraces his comforting presence and manages to plan her wedding - until they kiss.
When her fiance is away, they recconnect and Jane quickly realizes what she feels for th man she's planning to marry isn't love, but what she feels for Michael is.
But Michael believes he'll be taken away again on her birthday, just as he was when she was a child. So they end things again. But then...there is the happy ending that I simply adore. (sigh)