There was a couple sitting beside me at the coffee shop and the guy sat on the sofa that runs along the wall, and the girl sat on a chair across from him.
一つずつソファーがあるのではなく、奥が壁に沿って
長いソファー席だと想定しての回答です。
ーThere was a couple sitting beside me at the coffee shop and the guy sat on the sofa that runs along the wall, and the girl sat on a chair across from him.
「喫茶店で隣にカップルが座ってたんだけど、男性が壁側の長いソファーに座って、女性が彼の向かいの椅子に座った。」
sat on the sofa that runs along the wall で「壁に沿ってあるソファに座った」
sat on a chair across from ... で「〜の向かいの椅子に座った」
ーIt was disappointing to see a man take the good seat and let his girlfriend sit on a chair.
「男性が良い席に座って、彼女を椅子に座らせるのを見てがっかりだった。」
It was disappointing to .... で「…してがっかりだった」
ご参考まで!