Uh, your story is interesting in all, but how is your brother doing?
So far, great.
I use a simple drawing to point out why a 60+ person should not marry a young person, but no point in showing it to him. A person at the end of their “healthy adult” life span should not marry a person at the beginning of their “healthy adult” lifespan. The reason is simple: When your health starts going down, it goes down FAST. In a few years, one of you will be having drinks with the pool boy while the other is in a nursing home.