misfortunes never come singly; when it rains, it pours
A proverb meaning that bad things tend to happen one after another, especially when you are already in a weakened state.
Losing my job and then getting sick on top of that—when it rains, it pours.
雨で試合が中止になり、帰りに財布を落とすとは、まさに弱り目に祟り目だった。
The game was canceled due to rain, and then I lost my wallet on the way home—it was truly a case of misfortunes never coming singly.
Here 目 denotes a condition or situation: 弱り目 is a time of weakness, while 祟り目 is an affliction or further misfortune. The proverb describes another calamity arriving when one is already in difficulty.