We travelled from Melbourne to Perth and back last year when DD was 13 months old and she handled it fantastically . We took our caravan though, but with three kids it was kind of handy LOL!

She handled the long drives by watching DVD's, eating snacks and playing with a bag full of toys, etc. She loved nothing more than pulling everything out of a bag (it was filled with small toys, shells, stickers, etc) and starting all over again when I refilled it!

I don't think you're nuts at all, it sounds like fun