The meaning of "sadly seeing Yangliuchun" in ancient poems means: when I see willows in spring, I think of my separated relatives and friends, so I feel very sad. In ancient times, when willows sprouted in spring, they were broken down to say goodbye to relatives and friends.
This poem comes from Shi Jianwu's "Zaqu Song Ci·Willow Branches"
Original text: The roadside is near the willow spring, and every branch has been broken off. This year, I will return to my last place, and I won’t say goodbye to others last year.
Interpretation: Breaking willows to say goodbye. The willows on the roadside are broken year after year by people who leave. The willows can still grow new branches in spring. Although the willows are still broken in the same place as last year, they are already broken. It’s not about seeing off the people we left last year. The broken willows here also have a feeling that things are different and people are different, which makes people feel more sentimental.