I am 63 and got my licence a few weeks after my birthday this May, I started in August last year.
Took me ages to go solo,ie around 18 hrs but finished PPL in 53 hrs.
Instructors make a hell of a difference,it all depends whether you gel or not,they may be brilliant with other people,you may like them ,but they don't work for you.
As suggested try another instructor or even a different school but don't give up hope yet!
Lister