Absolutely, and when you're reluctant to have that difficult conversation, imagine that it's one of your loved ones who will be on board for that person's next flight. Knowing that, would you intervene?
It's also important to know that your offer of help is only as good as the person's willingness to get help. For some, they find rock bottom and live to see another day. For others, rock bottom ends tragically - as this one did.