如若不见亦不念如若相见亦相念
[rú ruò bù jiàn yì bù niàn rú ruò xiāng jiàn yì xiāng niàn]
It describes two situations - either meeting up again means mutual remembrance or failing to do so implies no extra thoughts for each other. The phrase expresses complex emotions toward others: when seeing each other frequently or re-encountering unexpectedly there might develop more attachments than before, however in case of rare encounter or permanent departure no special emotion would be raised anymore as if forgetting each other.