I am just astounded by the lack of empathy and the sheer meanness of some of the comments. This woman had the strength to come on here and tell people about her abuser. She was looking for a little support and advice. If you could not offer either one then why comment at all? She could be your friend, your sister, your mother or your neighbor. How can people be so small that they cannot imagine how it feels to be a victim? I've learned a few things and one of them is you don't give a man like that the power to continue to harm you or your children. She took the kids on a preplanned cruise and trip to Disney which is exactly what she should do. To stay home lets this dirtbag win and teaches the kids to be afraid and that might makes right. It took courage to come on here and admit what he did and it took guts to carry on as if he did not do it. If don't have something nice to say the please say nothing at all.
To the OP, I'm not sure if you will see this before you get back but I hope you and your kids have a wonderful trip. I'm sorry that you are going through this but it will make you stronger. Trust me on this. You will glad you did not let this monster take this trip and the memories you will make away from you and your kids.
You already got a lot of money saving ideas for meals. You will be fine on $600 with small kids. Coco Key where you are staying had a free breakfast when we stayed there as well as free water park and minigolf. If you have a kitchen get some food at shops like fruit,cheese,cereal and milk. I'm assuming you will have a rental car as it is off site. Try Sweet Tomatoes over at Crossroads. It is a buffet but all fresh fruit/veg, salads, baked potatoes, pizza, pasta,soups and desserts and drinks and it is cheap. I think it was $12 for me and my daughter in June. Have a terrific time.
Stay strong.