The least happy cancer is when they don't look nice. And since they are so emotional and irritable, they are more likely than other people to experience depression.
The Zodiac's control freak, Libra, is profoundly disappointed and even devastated by the fact that it cannot exert control over everything.
Pisces is depressed by family, but not so much by the family itself as by some families' inability to get along. They are strict upholders of tradition and order, and when their family life threatens to go off course, they do too.
Taurus is depressed by stagnation, and when they feel trapped, they spiral out of control. They also create this for themselves because they frequently settle for uninteresting settings that are comfortable.
Virgo, the master ruminator, experiences severe depression while reflecting on their own life. Additionally, as they are constantly reflecting on their life's highs and lows, this might result in emotional exhaustion.
Scorpio is depressed by fear and goes into a depressive depression cycle.
Gemini is depressed by heartbreak, especially when they weren't expecting it.
Aries becomes depressed when they are neglected, yet this doesn't happen often because they are so direct.