What 1960's movie was this?

I thought this was "I am curious yellow" but it seems like it wasn't. The plot was that a Swedish? woman whose husband had been tortured and killed by the Nazis, has sex with a man who turns out to be one of the Nazis who killed her husband. She then kills him.

Anyone know?

Thanks.

Think I have this one: The Night Porter starring Dirk Bogarde and Charlotte Rampling. If it is this one, they had a relationship in the concentration camp, where he both abused and protected her. They then meet in a hotel years afterwards where he has the job of Night Porter, and rekindle the relationship.