多情却是总无情，唯觉尊前笑不成。

蜡烛有心还惜别，替人垂泪到天明。

Rough explanation (accuracy is not guaranteed here. I explained it based on what I feel):-
This poem describes a scene wherein the poet (author) was about to part with his beloved. However, both did not display their sadness for the separation. The candle was the only one who can feel and understand their sadness and it shed tears on behalf of this pair of lovers till dawn.
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I like this poem because it beautifully paints the picture of two lovers separating for the night. In just a couple of words, the reader can feel the emotions that they were trying to hide and the sadness involved.