形同陌路 [－－－－]

Jyutping jing4 tung4 mak6 lou6
Pinyin xíng tóng mò lù

Definitions (CC-CEDICT)
  1. to be estranged
Definitions (Wiktionary)
  1. phrase, idiomatic
    to treat each other as passers-by; to act as if they are strangers