As I have two college age kids, this comes up a bit.
My son found himself in a bit of a jam from drinking a year ago. To the extent that I helped him out, he knows full well I get to offer my opinion/advice when I think he is being risky. But he also knows he is responsible for his behavior. My only open request to him is to let me know what is going on if it has to do with helping him with tuition and books.
Same with my daughter. She knows I am available but I am not a helicopter parent and she will have to take care of problems that arise. We have had good talks about independence and responsibility.