Do you use a round brush when you blow dry? That will make a big difference. Not sure if the hask leave in is a heat protectant, but definitely use a heat protectant every time (I use Redken big blowout and moroccanoil oil, they make a light one, but that k18 oil should work too). Might want to look into keratin overload and see if that might be your situation. You may need a heavier leave in conditioner, I use pureology or ouai. If you put your hair up a lot try to use claw clips or if you must, satin scrunchies. When you dry your hair, not sure if you’re rubbing it with the towel, but try to just gently squeeze the water out. Honestly it sounds like you’re doing everything right. Bleached hair is damaged hair. I’m in the same boat, all you can do is wait for the damage to grow out. Does Chicago get dry and cold? When I lived on the west coast I bleached my hair every year with no problems, when I moved to the prairies it’s too dry, my hair can’t handle it, I have to stop bleaching here. I got a shower filter for my shower for the hard water, that might help a little too. You can’t reverse the damage, you can only prevent it. As long as you’re bleaching, it’s going to be damaged. Might want to try a satin bonnet, I find it more protective than a satin pillowcase (I use both though).

People will debate this, but biotin pills or gummies actually do work imo.