Dolphin you do not say how old your children are.
Perhaps you could join a mother and baby club and get to know other mothers.
I am assuming you are a stay at home mum with some of your children in school.
Most cities have some sort of clubs sometimes attached to council or church buildings.
Writing in a journal your daily feelings may help if you are feeling low, try to plan and organize your day and think of the positive things in your life.