I'm not good enough for anyone
Why do you feel that way?
I let down everyone around me all the time.
If you think this way then you should seek help. A therapist can help you work through your insecurities.
Nah, I don't think I need help from someone who can't relate to me.
It's a common thing to feel this way, but it's good you realize this. I know you don't want to seek help but it's going to be very beneficial to you. Fixing your mental health will allow you to get back on your feet.