I had a similar experience with extreme anxiety, negativity etc. And like you, NLP helped enormously. I would encourage anyone suffering from this sort of thing to seek out NLP/CBT help and techniques. Just the simple act of noticing and catching myself thinking negative thoughts and reframing them helped... thinking "what's the positive way to look at this". There is always a positive angle you can find. A lot of benefit can be felt just being conscious of, and changing how, you view the world.