You made complete sense. I agree with Rip, in that you need to start with the small things. Try to find things that are small enough that you won't counter them and negate their goodness. Have you ever.... type things... have you ever posted to someone who needed support? Have you ever spoken to someone, or smiled at a child who needed it? Have you ever said "thank you" to someone? Those are all good things about you!

Next, continue to counter the negative, erroneous thoughts. It's a process.