I'd set up a generic named trust to claim the prize (provide at least of modicum of anonymity)...
Apparently the lottery already allows anonymous claims. The surprising part is how often we hear the real names of the winners in publicity when they can opt out.
I would only tell them I came into some money because I got lucky one night at the casino.
I find that odd given your comment about addiction in your family. If you are going to tell a white lie why not tell them you worked hard and got a bonus at work?
I honestly do not know what I would do. With that kind of money I think I would not need a financial planner but I would want a good tax accountant and a good attorney. I know a good attorney that I worked with at my former job. He is a bulldog business law specialist, and expensive. I would ask him to find me a tax person. Beyond that, I'd rely on them.
My original question was posed because of an NPR story I heard this morning. The lottery officials say that no one has contacted them claiming the winnings or claiming to represent the winners. That is not unusual apparently even after a week.