Don't give up!
I started out at 36 doing the upgrade at Prestwick.Despite being told I was too old to fly jets,6 yrs later I'm with Virgin.(I joined just after my 40th birthday.)
There were several oldies on my course and I dont know of any who didnt make it into the big time.Theres one FO at VS that I know who started out in his mid 40s. It all depends on the market for pilots and what experience level is floating around. Providing you have the ability there is no reason why anyone shouldnt do it.
Good luck