How to get over impostor syndrome re: PhD applications?

[MtrlHstryGrl]

Hello, everyone.

I am applying to doctoral programs this coming cycle and was feeling fairly confident until an email from a potential advisor about the amount of applicants that will be applying to programs this fall. I crossed the program off of my list, as the potential advisor also let me know that she would likely not accept a graduate student (especially not an early medievalist), but my confidence has been somewhat shot. How do/did you deal with anxiety and imposter syndrome in PhD applications? I should add that I am only applying to schools with which I have a good fit and professors interested in working with me, but I am still quite nervous.