在乎久了会崩溃想念久了会流泪
[zài hū jiŭ le huì bēng kuì xiăng niàn jiŭ le huì liú lèi]
Meaning 'caring too much will lead to breakdown; missing too much will make you cry,' it conveys vulnerability when love becomes overwhelming. It describes how emotions can become so intense they bring pain as well as comfort.