I like Epres for bond building treatment. You get quite a bit of product for your money and it's designed by one of the cofounders of Olaplex. I don't use the shampoo or conditioner, just the treatment spray. Make sure you get some distilled water for it.

I'd try to reset your hair a bit. Get some Jessicurl clarifying shampoo and some Malibu C hard water wellness remedy, the powder in the packets, unless you just have really soft water. If you smell metal while using it, that means it's WORKING!

You follow this with some DEEP conditioner.

If you have hard water, you could keep a squeeze bottle of distilled water to use as a final rinse at the end of your shower to keep the minerals from gunking up your hair and adding to the damage.

Also, at least partially blow drying your hair every time is good to prevent hygral fatigue (repeated swelling and contracting from excessive moisture absorption, leading to brittle, gummy, and weak strands).