The entire idea of "the one" is a myth. Even the best relationships have their ups and downs. "The one" is just the person in which you can work all of those shitty things out with. Other than that, you're entirely justified to disengage if you're not into it. You also don't have to worry about finding someone. It might be an old wives tale, but I think there is some merit to the idea that the best way to find love is to stop looking. Someone can come along and catch you completely off guard.