Can't find an old movie?

[qbix14]

Hi. I'm looking for a sort of old 80s-90s movie. I remember watching it when I was a ***. In the beginning a man and a woman (I think she was blonde) had sex, then after that she goes to the jacuzzi to bathe. While she walks to the jacuzzi the camera shows the man laying down on the bed, while she who is giving her back to the camera walks away in a pink bath robe, showing her ass. I think a man was sort of spying outside of the house while they had sex, but when they were done he left, and I think he was at that moment remembering his ex or something. Does anyone know what the name of the movie is?