Hi,OP -
I think your hair wants moisture and/or bonding. I find it can be slightly tricky because overdoing the bonding treatments can dry hair out further.
Do you tint, process, or heat style your hair? If not, it is more likely to be dry only.
For dryness, I like the moisturising shampoos, conditioners, leave in conditioners, serums, heat protectant sprays and above all deep conditioning treatments from Purology, Aveda and Philip Kingsley though the PK Elasticiser and Extreme Elasticiser seem to be Marmite. All are available online and the first two are available through salons.
For bonding I like Olaplex No 3 and No 9. The others in the home based system never did much for me but again, Olaplex is Marmite. Again available online. You can get a more powerful version of the No 3 treatment in a salon.
All these products are expensive compared to what is available in the chemist but you need very little of each, you don’t need them frequently, and they last a long time