Between dream and deed there are people in the way, and practical objections.
Madness string 105792
It's dumb either way; even if it were 'in your head', that would still be a legitimate psychological issue that's causing you distress and pain. It doesn't have to be physical to be a 'real' problem.
Only severely distressed animals, like severely distressed people, will relieve their distress pharmacologically if they can.