STEPMOMS: how do you cope with everything?

Depending on how old these girls are depends on how you can handle the situation. If they are young then just start and keep a routine in the house. If they are teens it's going to be much hard but do the same but sit down with the whole family not ex but your hubby and they other kids and set up rules that are to be followed and what will happen if they are not. By doing this you and your husband are working together and you won't be the bad guy here.