Its so weird you have posted about this because I am going through a similar dilema. i have already booked to go next october with DD6 who will be 7 then. the trouble is I am leaving behind DS4 and DS1. DH is more than happy to look after them but I know DS4 is going to be heartbroken when he realises what is going on. i have already paid a fair bit of money to virgin with a package deal and the only way I could turn it around and afford it would be to change my booking to a flydrive and book the hotel with disney seperately. the idea was to have a girls trip and go at a more relaxed pace. taking DS may result in tantrums and tearing from one attraction to the next. I don't think i can leave him knowing how much he would love to go back.
Sorry to jump on your thread, but while everyone is discussing your situation, I may just see if anyone has advice for me too. Hope this is ok,
Claire xx