This is a great post, and resonates with me massively! I have a huge fear of failure and I don't really know what it comes from.

Have you heard of 'Imposter Syndrome'? It's not quite the same, although I guess it's really relevant. My old boss told me I suffer from it, and so he sent me on a course that all focused on self-confidence! It was awkward and embarrassing at the time, but I think it actually paid off a little.