Feel like I raised a "fuckboy"

I have my son young. I was 14 when I had him and I honestly did my very best with him. Honestly he was going down a decent path until high school. He's 18 now and a lot of things he did I didn't even know about. He was sneaking out to party and drink and have sex. Now it feels like he has a new girlfriend every few months. And he smokes a lot of weed. So many mom friends I have had said jokes about my son being the guy girls date to piss of their dad's which honestly a lot of his girlfriends are girls that are rebelling against their parents and their parents don't like him. At the very least my son is nice and sweet people kindly. Part of me wants to talk to him because I'm sad about him becoming a fuck boy but I know I need to respect boundaries. I'm just sad....

@Kay he doesn't live with me right now. He's on his college dorm but he's only up the street