I'm like you. I tend to have more depression than mania, but always wind up feeling guilty for all the mistakes and things that I don't feel like doing.

One thing I do is make a to do list. I try to keep it short and doable. It makes me feel good if I can get at least one thing done for the day. It leaves me feeling a little more in control. Like today, I clipped my dogs, which I've been putting off. It will probably be the only thing I get done today, but it has left me feeling good about myself.