holiday syndrome

hol·i·day syn·drome

regression, development of diffuse anxiety, feelings of helplessness, irritability, and depression; said to occur in certain psychoanalytic patients before Thanksgiving and continuing into the Christmas holiday season, ending a few days after January 1.
Psychiatry A reaction seen in some patients under psychiatric care during the 5-6 week period from Thanksgiving through Christmas until early January, characterised by diffuse anxiety, regressive phenomena—e.g., sense of helplessness, possessiveness and irritability, nostalgic or bitter rumination about holiday experiences of youth, depressive affect and a wish for magical resolution of problems. The patient may act out some regressive phenomena with those close by, and may deny the meaningfulness of the holiday season, despite emotions and unconsciously motivated behaviours
Psychology An ad hoc term for the ‘antsy-ness’ manifest by various persons—e.g., homemakers ‘stressing’ about not having things perfect or students at all levels of education—before a major holiday