I want to be more than friends

Did you ever have that girl in school (or boy) that you wanted to be more than friends with. Maybe you were already friends, maybe you were just acquaintances. Then one day with a knot in your stomach you finally decide to take the plunge and put it all out there "I want to be more than friends", maybe they reciprocate and maybe they don't (more often they don't).

But what happens when you've grown up. You're older, you're wiser, in theory. Now you're faced with the same situation. You have someone that you want to be more than just friends with. What happens when that person is your spouse? What happens when you want to make it clear and yet you have that pit in your stomach like you were still in grade school?