Most of the time it doesn't though.
Today, I have been married to the same woman for 26 years. 4 great kids, lots of tears and laughs, through the good times and the bad. That still amazes me.
We dated for a total of 5 weeks and I only knew her for a couple of months before that. Everyone said there was no way it would work, that we would be divorced before 5 years were up.
All I have to say is, In your face doubters.
That and thanks to my wife for putting up with me for so long.