I want to leave my family?

Sounds like you are deeply depressed. Perhaps you should just see a doctor and see what (s)he says. And have you tried talking to your husband about it, only if you think it is the right thing to do. Obviously you know him better than anyone on here so you will be able to decide. I wouldn't leave unless you have exhausted all other options. Your kids will be incredibly sad and may never forgive you. So I would approach this decision as a 'no turning back' decision.