Feeling really down today

Sometimes, it's so hard to actually function.  I work so hard to make sure no one knows how terrified I really am of everyday life.  I don't leave my house most days, because then I feel like I might fall behind on housework, and then I might be a bad girlfriend and mother.  I don't like to be around people, it seems like I can feel them judging me.  I feel like everyone just sees me for the fat, not who I really am.  It's like if I'm going out, people are going to see me and think, why is she out? She's so fat, and besides, doesn't she have a family to take care of?  I feel like such a failure all of the time.  There are so many things that I feel like I'm not doing right.  I can't even fathom what it would be like if I were actually successful at something for once in my life.  I feel like if I could just do one thing right, I might have a chance, but it seems like I never get anything right.  I've never felt so useless in my whole life than I do now.