Thank you for your post. I have a honda hybrid, and I'm in a similar position to you. I bought the car about five years ago and with two kids, two in-laws and a dog I had to get something more accommodating. I use the hybrid for commuting to work and had to purchase a minivan.
When I tried to trade in my Honda for something bigger, the dealership only quoted a value 1/5 of the original cost. It sucks, but what could I do? I don't have celeb money.
Best of luck!