I don't really have a career as a jazz musician. I don't really have a career as a classical musician. I don't really have a career as a college professor, and yet I did all those things and I did them well. I put out some records in the 1980's and 1990's that changed the way some trumpet players played.
Create some psychological space between you and your project by imagining you're doing it for someone else or contemplating what advice you'd give to another person in your predicament.