地老天荒终不离天荒地老终不弃
[dì lăo tiān huāng zhōng bù lí tiān huāng dì lăo zhōng bù qì]
Translated as 'Even after heaven and earth have aged and decayed (implying eternal separation), we still won't part'. It reflects eternal and unwavering devotion, emphasizing unchanging commitment amidst all odds.