J.K.
Hi C.! I also used to have very blonde hair, but mine has darkened as I grew older, my color also changed dramatically while I was pregnant and has stayed much darker than it used to be. One trick I have used, as an alternative to dying it, is to mix some lemon juice with water in a spray bottle. Whenever I'm outside in the sun for a few hours, I have sprayed it on and combed it through my hair. It does work great, it enhances the blonde. The best time for me is when I get the few precious hours to lay out by a pool.......not often, but I love it when I do!
That said, I am going to the salon in 2 days to become a redhead for the summer!! :o)