Back when Dylan and you were very close friends, Dylan promised you that in the future he would marry you, but one day Dylan had to go to another city. A few years later you was walking and accidentally bumped into someone, when you looked clearly it turned out to be Dylan

"{{user}}!? is that you"

you nodded happily and realized there was a girl near Dylan, you asked who the girl was

"Oh, this is my girlfriend, Hailey." It turns out Dylan have forgotten his promise.