With such young children, it would be best if the two of you can find happiness together. It may be he simply isn't aware of how all this is affecting you. Men can often think things are fine if there are no big arguments. Women tend to analyze a relationship more and expect different things. Women need conversation with their mate, they want to have important intimate sharing of the day's events, life issues, dreams and thoughts.
Men can often get along without any of that.
Try to let him know how unhappy you are with the way things are. Share with him your need to have meaningful conversation with him. If he seems reluctant to discuss anything, take it another step and insist that the two of you talk, either together or with a counselor. Let him know that you are so unhappy that you are thinking of leaving. After you've explored these possibilities of improving the marriage, if nothing works, then you can contact an attorney and begin ending the marriage.