Well, we each have our own story. I was 36 when my son was born. We had been married for 3 years by then. My wife stayed home for the first few years and then we put him into preschool. We limited tv, computer and internet access. I coached him in tball, soccer and basketball, until he showed no interest. (and I wasn't a raging sports dad either). We went to all the teacher parent conferences.
In other words, we did all the things that we were shown how to do by our parents.
Two months ago, we asked our son to find other accommodations. He is nineteen. While he had a minimum wage job at CVS, he seemed comfortable with that as a life goal achieved. His room smelled like bong water, he would come home in the middle of the night and wake us up while preparing his "evening meal" And he had trouble understanding why we had an issue with him sneaking his underage girlfriend into the house.
I was really stupid at nineteen, but the Navy cured a lot of that for me. He wouldn't even pass the piss test.
Sorry for venting at you all, but it won't work unless I hit the send button.