我曾深夜念你心如刀割撕心
[wŏ céng shēn yè niàn nĭ xīn rú dāo gē sī xīn]
This username translates to 'Thinking of you late at night, my heart feels as if it's being slashed'. It depicts a deeply sorrowful feeling where someone misses another person intensely to the point of emotional pain.