"Butterflies can't fly across the sea" comes from the song Butterfly written by Lin in the album Crazy Foreigners released by Faye Wong 1999, and it is also the mandarin version of the Cantonese song Postman.
It means: beautiful things often can't last forever, which is a very pessimistic statement.
The person who said this sentence may have a tendency to be pessimistic and frustrated in reality, so he made such a sad voice.
Extended data
The novel "Butterflies Can't Fly Over the Sea";
Butterflies Can't Fly Over the Sea is a youth novel published by Relay Press on June, 2004. The writer is Yi Shu. This book mainly tells the story between three equally beautiful girls-Su He, Lu Dandi and Du Weiwei.
Surh was robbed of the position of the host and her boyfriend Long Ze by the gold medal female anchor, and met The Last Month Of Summer, a simple and kind rich boy, only to find that he and Long Ze are extremely good friends; Although Lu Dandi looks strong and savage, she is very dependent on her boyfriend at heart. Unexpectedly, the seemingly perfect relationship also lurks a crisis. She gradually realized that the people who can be together in the end are often not your favorite, nor your favorite. Du Weiwei finally failed to win a personal war. She hates that she never really loved or even missed it.
Time never stops and keeps moving forward. Love and friendship are still in the lives of these three girls, coming and going. No one knows Sue. He has been hiding a painful secret. So, everyone asks themselves; If you can't fly across the sea, do butterflies still need to flap their wings?