Oh, Teresa, I am so sorry. We've never talked before. My name is Jenn. I have been in that hell that you're in now, when I thought there was only one way out. I don't know your situation, and I've never been the type to think that things will always get better, because for some people they don't. But...for most people they do. They got better for me, and I swear the words you're writing could have been written by me three years ago. I can't say I would've blamed me if I had done something terrible to myself, because I was so down and my life really does suck sometimes. But at the same time, I am SO glad I didn't, because I got better, and life got better, and I have spent three more years with people (and two dogs) whom I love. It hasn't all been fun and games; life is hard. But I think you have to live it for the small moments that bring you joy. And I do believe that this, too, shall pass, and you will have some more moments of joy in your life.
And I know you said not to answer this question, but you are not a terrible person. You know how I know? Because you are asking yourself these questions and feel so bad about yourself--that is precisely how I know. Believe me when I say that the truly awful, evil people out there are that way because they never bother to ask what is wrong with themselves, and they can never admit fault. Anyone who beats him/herself up the way you are must at least care about whether he or she is a good person, and that's the most important step towards being a good person, in my mind.
I'm also not the type to gloss over things and say you have nothing to be depressed about; the world is a sunny, happy place; snap out of it; life is always good, etc. But I do think that most of the time it is worth living, despite all the hardships it brings. Please, I don't know if what I've said has helped at all or made things worse, but please, please, please check back so we'll know you are okay, if not mentally, at least physically. Mental states CAN change, but if you hurt yourself that won't ever change.