不是我不爱你只是你不爱我
[bù shì wŏ bù ài nĭ zhĭ shì nĭ bù ài wŏ]
This phrase articulates mutual misalignment of affection wherein the subject clarifies it's not about lack from their side ('not that I do not love you') rather expressing that reciprocity doesn't exist because the other party does not share same emotional depth causing unrequited feelings situation.