How long is a will valid in the state of Indiana? Does divorce make it no longer valid?

Each state is different but I suspect my California background will work here. A will is valid forever.  Divorce probably makes any provisions, where the ex is named, as if the ex wasn't named. That is, the ex is probably treated as being pre-deceased. However, it's always a good idea to get a new will when you get divorced to be safe. Good luck.