It takes a village to raise a child, as the saying goes. To share the load, see if you can arrange regular play dates for your child with other families -- neighbors, friends, or parents of your child's classmates. In addition to enhancing your kids' social lives and giving you a little break from the responsibilities of parenting, scheduling regular play dates could lead to new friendships for you.
This kind of connection with other parents often has the potential to extend beyond graham crackers and LEGO sets and into a source of moral support in which you share some of the same problems and stress factors. Just make sure that your new pals are people you trust -- and stay aware for signs that your children may not be enjoying these play dates as much as you do.