What do you do when your heart says no but your mind says yes?

Here's a scenario:
You have the opportunity to have everything you want, materialistically. A house, medical, car insurance and everything under the sun that an adult needs completely paid for. The only thing you would ever have to pay for ever again is gas (car) and cell phone bill.
But there is only one catch.
You have to marry this guy that you've dated for a few years but you're not entirely sure you truly love him, your family hates him and he's going to be gone all time because he's in the military and could possibly die at war.
What do you do?

Your master stays in your own self. Just do what your heart says, not what your desires says.