Truffle, you need a hug! And you need some new clothes.
I do that too--don't buy myself anything new, and then hibernate, because my old clothes don't fit--but that makes you feel worse about yourself, which is something that leads to overeating. Target has some cute things for under $40--maybe just one nice outfit, that can be your "going out" outfit?
And I know, sometimes getting one day under your belt is the hardest thing, but after you do, things look a whole lot more promising. So just focus on one day. Make that your entire goal.