How Do You Know if You've Met "The One"?

Is it because you're head over heels? Is it because she can cook? Is it because you love his style? Is it because you like the way she looks even when she's in a t-shirt and jeans, with no make-up? Is it because you can blast Christina Aguilera at full volume in the car and sing along while doing so, and he doesn't mind? Or is it just the right time to settle down? Or have you been smart about this, have you factored in everything from how they are with finances to how their family background shapes up? Here is your chance to share, whether you're happily married or think that in one distant day you may be happily married and have some sort of inclination of what you think you might look for in that person.