I believe everyone experiences a "fear of success" many times through out their lives. I experienced my fear of success when I left my current job to start up my Money Management, Registered Investment Adviser firm. I feared losing a "stable" job, questioned myself many times as I had turned down several very high paying jobs in order to pursue that opportunity.
What helped me was playing out the "worst" case scenario in my head of what could happen. Once I acknowledged that possibility, all other outcomes were not that bad after all. After moving forward I now love my job, I am earning spectacular returns for my clients, and have never been happier.
In my opinion, the greatest risk in life is not taking any risks.
Best of luck conquering your fears Revenant, don't let your fears get in the way of your success.