What is the meaning of 忽爾間 in the song "說散就散"? I just learn Mandarin from songs whenever I find the time. I have recently discovered this JC's song called Shuo San Jiu San. In the last sentence of the last paragraph of the song, which goes"因為成長 我們忽爾間說散就散", I understand most of the characters' meanings except 忽爾間. Google translate says "time flies" but I don't think that's the case. My personal translation of that line would be " because we have all grown up, let's break up if you say break up". I have no idea where that 忽爾間 would interact with other characters.

Lyrics link - https://musicacrossasia.blogspot.com/2017/10/jc-shuo-san-jiu-san-lyrics-with-pinyin.html
I think it is more common to say 忽然间 than 忽尔间，but it is a song!

忽然间他看见了我,就往回走, 伸出手来.
Suddenly he saw me, and walked towards me, holding out his hand.

因為成長, 我們忽爾間說散就散
Because (we had) grown, changed, we suddenly said break up then broke up.

There is also 忽而 。。。 忽而，but that is a different kettle of fish!