It's not that they're "undatable". Everyone is datable. It's just that there it is a rare thing to feel that rare undefinable connection with someone. There is someone out there who would find your undatable person quite datable.
You are NOT too old to date! You are adorable, intelligent, and fun. I'm older than you and I date. It's fun. I keep my expectations in the "fun" mode, without the pressure of anything else, and I've had all types of relationships and developed wonderful friendships with the most amazing men.
RE: Dating in late age
...then roll over and go to sleep.