Ohhhh, I'm so sorry to hear this has happened to you.
I agree with the previous poster. I would strongly advise you to NOT get a relaxer. If you apply a relaxer to your hair in its weakened condition, you might damage your hair.
To get rid of the tangles, soak your hair in a good conditioner with a lot of slip (Aussie moist, Hello Hydration, whatever works for you) mixed with extra virgin olive oil and put on a plastic cap for about an hour or two.
Then separate your hair into sections and detangle one section at a time. Be patient and gentle with your hair and take your time. Hair that has protein overload needs TLC.
To restore the balance in your hair, do a lot of moisturizing DCs...maybe once a week (more if you feel your hair needs it). Use good ones like Aubrey Organics Honeysuckle Rose, Jessicurl Weekly Deep Conditer, Hairveda's SitriNillah, etc. Mix the dcs with honey, EVOO and slap it on. If you have a hair steamer, you might want to incorporate it into your DCs as well.
Other than that, keep your hair moisturized, seal with your favorite oil, bun it, and leave it alone.