Optirectumitus
op-ti-rec-tum-it-us, noun, 

1. An ambiguious mental condition which manifests itself by outbursts of negative thinking and behaviours. Experts have hypothesized that the condition peaks whenever neuro-transmitters from the optic nerve cross the path traveled by transmitters from the  nerves of the anus or other rectal areas. The most commonly observed symptom is an obvious disposition by the sufferer that includes a severely excremental outlook (shitty-outlook) on life and living.

2. Negative thinking; hopelessness.
Johnny thinks his life is over. He is obviously suffering from a bad case of optirectumitus.