I was listening to a sermon by Matt Chandler awhile back where he mentioned something about the typical young person dating mentality that says, "I'm looking for that one person out there whom I can really love to be spouse. The one person God made for me who suits me perfectly." And so on. Like trying to find a unicorn: there's one out there somewhere. You just have to find it and tame it. But no other animal will do in the mean time. Chandler says it's bogus, then says something great about his wife, Lauren: "You know how I know that Lauren is the one for me? Because I'm married to her." Exactly. Commitment is the key, not chemistry.
There are a thousand ways I could take a post like this, but the best is probably to point you to a hilarious and spot-on critique of that mentality by an Australian musical comedian named Tim Minchin. Let me note up front: while this video has no objectionable content, if you start following the links at the end of it you'll discover that most of his other stuff does.
In any case, enjoy Tim Minchin's "If I Didn't Have You".