This sentence itself comes from Zhang Ailing's Love in the Whole City. The original sentence is: the moon in the sea is the moon in the sky, and the person in front of you is a sweetheart. Always be a spectator, but people are people in the play.
There are several words different from this sentence, but the meaning is the same.
This sentence shows us what the feelings in reality are: love in the mirror is too illusory, and the company of a porridge and a meal is the most real and reliable.
Everyone has a different understanding of love, but I agree with the meaning of this sentence.