Definitely cut out the damage, be sure your protein is hydrolysed so it absorbs and don't overdo protein. Coconut oil is wonderful for damaged and porous hair.

Try a gel containing a fair amount of humectants like propylene glycol, assuming you are in the right climate for that - maybe Curl Keeper - or even a curl cream or make an Ecostyler custard with any gel plus a little oil (see YouTube). Mousse is often not enough to 'glue together' damaged strands to make clumps.
2a-2c, medium texture, porous/ colour treated. Three years CG. Past bra strap length heading for waist.

CO-wash: Inecto coconut/ Elvive Volume Collagen
Treatments: Komaza Care Matani, coconut/ sweet almond/ fractionated coconut oils, Hairveda Sitrinillah
Leave in: Fructis Sleek & Shine (old), Gliss Ultimate Volume, various Elvive
Styler: Umberto Giannini jelly, Au Naturale styling gelee
Flour sack towel, pixie diffuse or air dry.
Experimenting with: benign neglect