断情陌生人
[duàn qíng mò shēng rén]
Literally means 'estranged strangers.' The phrase suggests the user views people (perhaps even close ones at one point) as estranged strangers now. There's a sense of emotional detachment from others or from the past. It could be used by someone who is distant in nature, or has been through a painful experience leading to estrangement from their loved ones.