Aww honey, I relate to a lot of your feelings. I've felt pretty worthless before, no use to anyone around me, but I now know that was the depression talking. I don't think what you feel about yourself is accurate. I think you just need to talk to someone. You also probably need a change of pace. I am absolutely sure your family would be sad if you were gone. No money could replace their daughter, wife, and mommy.
Be who you are and say what you feel, because in the end those who matter don't mind and those who mind don't matter. - Dr. Seuss