Do you think you married 'the one'? Do you ever have doubts?

I so want to answer this question. This is something I always think about - what if I don't marry the right person? What if I marry a wrong person? What would happen? Would I be able to change that ever? What if I had to stick with that wrong person? Damn. It's horrifying even to think of. But luckily, am not married yet.