What you really need is someone to race against.
I have enjoyed the last few years locked in a no-holds-barred struggle with my younger brother. It didn't matter how many were in the field just so long as I beat him!
I'm 67 and you lot don't know what old is! Nobody has mentioned arthritis yet! I think I will have to stop when the arthritis in my thumbs stops me putting the tyres on the rims! ;-)
So you are nowhere near old enough to give in yet. Just live for the day when you improve in each round of quallifying and manage not to strangle the nine year old who has T-boned you after you just lapped him in the F Final!
Perhaps the BRCA should stop pandering to the young and introduce V60 and V70 categories.