四面楚歌 (しめんそか): being surrounded by enemies on all sides; being betrayed (forsaken) by everybody

being surrounded by enemies on all sides; being betrayed (forsaken) by everybody

Xiang Yu heard his enemies singing the songs of his own homeland and knew he was surrounded. For the moment you realise nobody left in the room is on your side.

The same saying in Chinese: 四面楚歌

A Japanese proverb (ことわざ)