Kissing a Fool (1998) on Netflix

Jay and Max have been best friends since childhood. Max is the party type, seeing many different women in a short period of time, doesn't want to settle down. Jay is just the opposite, he's looking for love and he thought he had found it with Natasha. Unfortunately, she dumped him long ago and he's been in anguish for a year. Jay introduces his editor, Sam, to Max. They go on one date and immediately fall in love. Within two weeks they're engaged. In order to see if Sam will be faithful, Max asks Jay to test her. He wants Jay to try and get Sam into bed. After some weeks and spending a lot of time together, Sam and Jay discover they may be falling in love.