那段爱海枯石烂这段情石沉大海
[nèi duàn ài hăi kū shí làn zhè duàn qíng shí chén dà hăi]
That love lasted until the sea dried up and the rocks decayed (a phrase meaning true love lasts forever). But this relationship was lost like a stone dropped into the deep sea without any waves (implying the current romance seems not so lucky as expected, just gone without a word.)