Need to know the name of this movie, pretty please!

I am looking for a foreign film I saw years ago and because it is foreign and I do not know the title, I am having a very hard time finding it. I was young so I didn't get the whole plot, but from what I can remember. A young man comes to live with a family and the wife starts up an affair with him, in fact, I seem to remember him sleeping with a lot of people in the town. There is one scene where the husband spies on them but does nothing. At the end of the movie, the husband and the young man are in the basement or cellar and the young man seduces the husband and starts having sex with him for like 2 seconds before the husband freaks out and kills the guy. It ends with what seems to imply that the wife helps the husband cover up the murder. I believe they throw him down a well? I really can't remember, I was much too young to be watching a movie like that but it stuck with me and now I want to see it again so that I can actually understand it this time. lol... I believe it is a french film, but I could be wrong. Does anyone know this movie???

P/S- Hello all! My name is Lux and I just joined today.

Nothing at all? I feel like I am never going to figure out the name of this movie. If it helps, I believe it is a French movie, but I'm not sure. Please help, it's driving me crazzzzyyyyyy!!!

Nettoyage à sec (1997)

IMDb Page | Review | Analysis + Spoilers | Original Trailer

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Thank you SO SO SOOOOO much! I really didn't think anyone would be able to help me. You're awesome!!!