悲伤逆流成河眼泪顺流成伤
[bēi shāng nì liú chéng hé yăn lèi shùn liú chéng shāng]
'Sorrow turns upstream into a river, tears go downstream causing injuries.' Portraying extreme sorrow that flows back like a stream of water flowing in reverse direction while tears run down the face as usual leading to hurts.