i recommend cutting off the damage and starting from scratch. the key to having long hair is not damaging it in the first place. if you don't ever damage your hair you'd be amazed by how thick and long your hair can get in a relatively short space of time.
When your hair's a TWA you really should just leave it alone and ignore it, only washing and moisturizing on a need to basis. but when your hair starts getting to NL stretched and SL then you should utilize either curl defining or stretching methods to keep your curls intact so that they don't tangle and matt and knot. i've had that experience and it's awful. Also start protective styling around this time.
I recommend too avoiding heat altogether until you get your hair to where you want it, and even then when you do implement it be cautious. as you've seen, it is very easy to damage our hair.
i suggest using roller sets or flexi sets or curlformers and things like that if you want a straighter texture without heat.

If you want to blow out your hair, generally blow dryers are fine and much more gentle on the hair than flat iron, but you want to use the right technique for that.
Practice leaving your hair alone for long periods (benign neglect) as your hair gets longer in protective styles to ensure optimal length retention.
Products don't matter- just find something that keeps your hair moist or a routine that is built around moisture and protection.
Personally the only product i ever use is conditioner, and that only on wash day. it serves me well. My hair is about APL now and i last cut it 4 months ago to CBL, if that gives you a picture of how well my own routine works for me.
Also, have patience. It will take a few months to a year or so to get the length that you desire, depending on if you cut. if you cut, it'll take you about two years going from a fresh shave. enjoy the ride and try not to think about your hair too much over the meanwhile. you'll get there.
good luck! i've gone through what you have, if that helps. :)
i can totally relate to being one of the few naturals around. i don't even know anyone who's natural in my own personal circle except my aunt and grandma, if they count lol they're old phogies. but of my coworkers i'm the only natural- the rest of them have permed, breaking short hair except one, whose hair is healthy relaxed same length as mine. and there are tons of natural girls on campus but...they wear their hair a lot differently from how i wear mine so, eh. i feel like a fish outta water around other naturals sometimes.