Purim is for alcoholics.
Pesach is for obsessive compulsives (OCDs).
Shavuot is for insomniacs.
Lag B'omer is for pyromaniacs who weren't satisfied with Hanukka.
Tisha B'av is for manic depressives.
Rosh Hashana is for people who obsess over dying.
Yom Kippur is for anorectics.
Sukkot is for the homeless.
Simhat Torah is for those in their happier stages of bipolar.