Okay, that word may be a little extreme. But the feeling of being unlovable, not good enough, and simply outside the bounds of acceptable comes around, even to people who are card-carrying self-help helpers.
Here's something I've learned; when I lead with my vulnerability, (not everyone, but) many people meet me with a hand to hold and a shoulder to cry on. Rather than making people go "ewww" (usually) the unvarnished truth allows them to be honest themselves. It's a relief to them that I can acknowledge our shared truth; we all feel like losers at times.
Asking for help when you most need it can feel overwhelmingly risky. BUT. Do it anyway.
If you want kindness, admit you could use a little. It's amazing how people want to dry your tears and offer their arm. Showing compassion invites agreement that you are really not as bad as all that. In fact, you're loved. Even if you don't feel you deserve to be.
People have an overflowing well of goodness. But they sometimes don't know how to offer it. Give them a way in. Admit you're a loser, just like everyone else.
We are flawed, fallible, imperfect people. At least, the sane among us are. Next time you feel like a garbage person, realize that almost everyone you know has dragged themselves off to their responsibilities feeling the same way. They've shown the ultimate bravery; continuing to try.
The trick is to keep risking, keep living, while allowing that there are ditches beside even the most beautiful road, and one of these days, each of us has our turn falling in.