Try not to compare yourself with others. You seem to be quite focused on the idea of accomplishment.. but I am not really sure what that means. Your value as a person is not measured by what you achieve, but by who you are. I think when we don't feel good about who we are we wish for achievements to show to ourselves that we have some worth. But actually they don't matter even if you have them if you don't love yourself inside.
I haven't figured out how to do it myself yet, waiting for therapy.