花开花落自叹息人来人往剩自己
[huā kāi huā luò zì tàn xī rén lái rén wăng shèng zì jĭ]
Here it conveys that one laments their loneliness as the surroundings change constantly. Flowers blossoming and fading away represent seasonal changes while people come and go, but they always end up alone.