Have you tried co-washing? that's using conditioner to wash your hair. Wen and Pantene Co-Wash are two named brands I know of and, Pantene is less costly. You can use any conditioner but, you'll have to use a lathering shampoo more often if the condition has carnauba in it - that's a wax and, it builds up faster.
The sulfides in lathering shampoo are what makes hair frizzy because it strips too much natural oil away and, roughs up the cuticle of your hair so, use those only once every 4-5 shampoos, when your hair starts feeling to heavy, use conditioner only otherwise, just leave it on for one minute and rinse, you're good to go or style your hair as you like.
I have naturally curly, thick hair and, I fought the frizz for years until a stylist told me about co-washing. no more frizz, even in high humidity or on rainy days. The cool thing is, if I want the fluff for a beehive or other teased style, all it takes is a double wash with lathering shampoo and, because I don't have split ends or damaged hair anymore, it fluffs up perfectly with little to no actual teasing then, one co-wash and it settles right back down to sleek and shiny.
Another trick, if your silver gets looking dull or a bit yellowed, mix 2 oz. laundry bluing into 4 oz. cool water, wet your hair with that and leave it on for three to four minutes, then wash as usual - beautiful silver hair again and, a lot less expensive and gentler than bleaches or peroxide.
