Hi, you are never too old to start. I started 30 years ago with a 16' Comet, then 2 years later moved to a 22' Oday with a 1 yr son. My daughter, son & wife tried it over the years with my wife even in chartered 30s' boats in the Chesapeake but did not get in to it. The result was I sailed for 28 yrs just in the Barnegat Bay about day solo about 60% of the time. But I did bareboat about 13 weekends 30'-40' with guys from work in the Chesapeake & just dreamed about a BVI week. Last August, being alone I bought a 28' Oday with solo being most of the time. Since I am retired I solo maostly on week days. I think that I could have goene a couple of feet larger . I do have Sarah (Self-contained unit for Automatic Response at the Helm) to help on tacks & raising the main. I have a cradle in the slip to control the bow if there is wind for solo docking. I met a guy this year that soloed his 42' from Norfolk to Cape May. It is better to grow into a little bigger than comfortable boat than to quicky outgrow your existing one.
I am 65 but feel younger. A small number of guys in the marina are in their 70s & get alone with minimum help for day sails in 30' to 37'. I have not tried to weigh anchor in moderate wind solo yet.
My peers are dropping by the wayside. "Don't wait for your boat to come in, Swim out to it!"