Don't give up. It is not easy being a parent especially today with so much taking your child's mind from the things of home. You are the leading force in your home, you have to take control of what goes on in your home.
When we sign on for parents no one gave any of us a handbook for us to follow. ( accept the bible) and that is sometimes too hard to follow. As parents we can't try to be everything to everyone and we can't be super -moms. Don't have your children in so many activities and you are the only parent running around with your head cut off. Narrow things down to a few that are manageable. Make sure ther kids that are 9, 10 & 12 are helping with chores; picking up after themselves, they are old enough to help. Don't try to buy the whole store for Christmas do whaat you can and iwthin your financial means. Be honest with your children and let them know you are not rich and can only do what you can. When you talk with your children and be honest they understand.
If parents are helpful at all enroll them to help when they can. Get involved in your local church and pray and don't hesitate to ask for help. Also local mom clubs takes the edge off you may find someone who you really click with who may be a help you can barder some time for babysitting, or taking the boys off your hand for an hour or two. Enroll fiiends , and family, let them know you need a break from time to time. Take a brisk walk when the kids are gone, don't use the time to work spend with friends and take in a movie or hot bath. You deserve it