I have been coloring for years as well. My original favorites were from the L'Oreal line of color treated shampoos. Anything from them I thought worked fine.
Then, quite by accident, I stumbled on Pantene Sheer Volume Shampoo, the clear one, doesn't really have anything in it. I have found that this shampoo and conditioner kept my hair color longer than anything. That includes the off the chart expensive brands, including Wen, Oribe and Acqua Di Parma.
For the price it is worth a try.
"Cats are poetry in motion. Dogs are gibberish in neutral." -Garfield