what would Jesus do?

hypothetical situation.

let's say someone is in need of your help, but they don't want it. what would you do? it's someone you care deeply about. and you know that they're making a big mistake. the mistake they make is irreversible. you've already tried to help them by giving them advice but all they do is reject it. do you just let it go cuz you've tried and they have to learn for themselves? it's a mistake you know for a fact they won't be able to live with and you can't live with for letting them do it. i'm talking about a big decision, like jeopordizing your health, gambling an obscene amount of money, getting married to someone you know won't last, etc.