this is a very beautiful and accurate sentence from a ancient poem《独坐敬亭山(translated directly: sitting and enjoying the great view of Jingting mountain by myself)》by libai(李白). if u want to understand this sentence throughly , i suggest u read the origin poem bellow first:
独坐敬亭山
〔唐〕李白
众鸟高飞尽,
birds flying high, embracing the sky
孤云独去闲。
lonely clouds being , leisurely going
相看两不厌,
just Jingting and Me, each other we admire
只有敬亭山。
the only beauty i can see, is jingting in front of Me
the 3rd sentence means that: Jingting mountain and i are both having a look a each other. i was absorbed by the beauty of j, and my unique personality makes j also interested
here is a metaphor. j is likened to a beautiful girl. libai is watching her and she is also watching libai. it accurately and vividly shows j has such beautiful scenery that libai was totally absorbed in it.
now 相看两不厌 is also used to describe lovers who love each other deeply
the translation is from my self. i just want to keep the Chinese taste and sense of beauty. it could be not that accurate. i wonder if mind it and i hope u can also feel the beauty of this poem