This sounds familiar as I had something similar in 2003. It is normal for docs. to warn about the worst possible and if the result is not as bad, the patient isn't upset. My guess is you'll come out OK.
If your cancer is not from HPV, you'll need to avoid alcohol. Just a little will kick the cancer off again. If yours is from HPV, I understand alcohol is not the same problem.
Assuming you are treated at a CCC you should come out of this better than your worst fears.