Here's the problem. You don't know how long you will live or what will happen to you during that time. Therefore, the smartest thing to do is protect what you have as long as you can. Don't use up your money under any circumstances unless there is just no choice.
One thing to think about is becoming a full time RVer. This lifestyle isn't for everybody, but it can save you a ton of money...no taxes, minimal upkeep, lower utility bills, etc. I'm going to write a hub about this soon as I have been a full timer, and it worked well for me.
I can't think of any normal senior who doesn't worry about money, so you are not alone. You have no control over what will happen health wise, but you CAN limit your liability in other areas. For example, if your roof goes, it's very expensive to replace it. In an RV, well...worse case scenario is that you get a different RV, which still will cost less than replacing the roof on a house. Less is often more.