No offense brother, but who wears the pants in the family. It sounds like you lived fast and free in the past and now have to pay for it. As long as you are not continuing that expensive lifestyle then what is the big deal.
Let me get this straight. You currently own a paid for NSX and three bikes worth a total of 10k, plus you pay $1000 per month to pay off your debt? Am I hearing or reading
you correctly? Then what the hell do you need to sell your NSX for anyway besides the girlfiriend wanting complete control. Sell your bikes and continue paying $1000 and you will have this paid off in less than ONE YEAR. The only reason to sell the NSX is to pay it off immediately or unless your car needs a lot of mechanical work.
My wife wanted me to sell my car too, but since I am the one who pays for it, she doesn't much of a say in the matter. This is not the price of love. Love is about compromise and not control. We all moved out of our mother's house and we don't need to bring on another one.
Is your debt something that she is going to have to pay for and that is why she is reacting like this? Would a woman sell her Prada shoes or a Gucci purse to get some extra money after it is paid for? NO!
Now it would be a different story if you were falling behind because you were paying a lot of money for the NSX, maintenance, or just getting ready to buy it. Then not a smart decision. If you can afford the NSX, $1000, plus living expenses by yourself, then it should only get easier by combining two incomes together will it not? Bite the bullet for a year and pay for your mistakes. The NSX is not one of them. Since it is about compromising, then get a second job bartending or something two nights a week to pay it off faster. If she was truly just being responsible, then she would understand that, but it sounds like this is coming from a selfish point of view.