他未爱我入骨我却待如命
[tā wèi ài wŏ rù gú wŏ què dài rú mìng]
Expresses an unreciprocated love or a kind of unilateral obsession, meaning that even though one person didn't love them so much, they are still committed fully - 'Despite him not loving me deeply, I treasure his love like my life'.