There is no law that says it has to change. You could just be a serial dater for life if that is what makes you happy. Or stay single for stretches of time. Monogamy seems over-rated, anyhow. Finding one person and trying to stay with them for an entire lifetime seems like a rather lofty goal, and I'm not even entirely sure what the purpose of that is. Sure, it has it's benefits; but it has obvious downfalls, too. Just do what makes you happy and try not to feel pressured into doing what society tells you you ought to do.
Maybe because your attraction towards woman are only physicial &you find out you have no commom ground interests or... you don't try to even establish a conversation enough to take it any further than just a casual temporary person in your life.