Depressive Curse

Origin
The Breakup Curse (now amor damnum) is a curse to end a relationship. This is an unforgivable curse. "A loud voice behind me, was Lord Voldemort, yells the incantation: "Engurgio!""

- Voldemort, attempts to curse Christopher Lewis

* used with permission by the Ministry of Magic

** used with legal permission in battle

*** Unintended Victims 

~ Imperiused Casters

Treatment and Health-Related Cases
There has been cases where witches and wizards have been cursed multiple times at once, putting them in a medically-induced breakup, and requires medical treatment, which are only available in wizarding hospitals like St. Mungo's Hospital of Magical Maladies and Injuries.

Treatment Services for Muggles
Since St. Mungo's Hospital is not accepting Muggles (technically is no longer since the 1700s), the curse is permanent and may inflict lifetime consequences, which is why the curse is unforgivable.

Withdrawals from the Curse
This curse does have side effects if not treated immediately. For instance, victims like Christopher Lewis had to suffer lifelong damages from the curse he got during his second year. The symptoms are very severe, and is likely to cause death. Each phase depends on the time you were under the cruse effects. The longer you wait for treatment, the more severe it will be.

Withdrawal Symptoms
These symptoms appear a week to one month after treatment, and usually wears off after six months to a year of that.