wow - you poor thing.
you sound like you really love your girls.
Forget the toilet training thing, kids develop differently and many go along way past 24 months without toilet training - even my paed told me to wait and my daughter is almost 2.
I hope you can get some help with the kids, it must be really tough in your position. Maybe there are some local resources that can help you out - i know some local councils offer in home child care assistance for free, maybe call your council to ask if any of these services assist in your area - it might give you a bit of a break.