扰我清梦一场予我半世凄凉
[răo wŏ qīng mèng yī chăng yŭ wŏ bàn shì qī liáng]
It refers to a scenario where the person's sweet dream was disrupted, which led them into long-lasting sadness (literally half a lifetime). It could indicate an important event or relationship that has been abruptly cut short leading to prolonged emotional distress.