I'm sorry you are feeling like that, I also can relate to what you said, I think that I am a good person (I hope so) I try to be there for anyone who needs help or advice and I try to be polite and do other good deeds without being asked to. I've had people tell me I was here for a reason, to help people and change lives but it doesn't seem to make any sense because I can't even be here for myself and the universe seems to want to put me through every test in the book.
I hear you that you feel alone and I can understand that too, but hopefully with SaSu you don't feel as alone as you were before it. I can personally say even though reading through the many threads can although be very sad, it is comforting in a messed up way to see how many people are just like me.
I know I'm just a random person on the internet to you, but if you need someone to ask you how you are doing, how your day was, or all the small things in between, I would love to be that person. No one should feel like shit all the time I wouldn't wish it on anyone, I hope you knowing that you are not alone helps a bit. I plan to try to CTB in a month or two but in the meantime I'll be here for you.