K.
Well...
I returned to work after 3 years at home. Albiet, not by choice. My husband sustained a career ending injury and that left me required to return to work to keep a roof over our head.
The first few weeks were very tough. But... your kids are old enough to contribute. And quite honestly, "I don't feel my spouse and kids will be willing to help" is hogwash. You don't have a choice in returning to work and they, therefore don't have a choice in helping to fill the gap when you are gone. Families are a unit... that help each other. It is not your JOB to do everything, when you have to work on top of it.
I strongly suggest you start a chores chart and equally divide out what needs to be done. Your children are old enough to actively help in the household management, as is your spouse. When I had to return to work, my spouse contributed 50/50 with me. (our daughter is only 3) There is absolutely no reason to settle for no contribution from your family, especially given your childrens age.