For me it was really meditation that did the trick. I used to think that I was rubbish at it because I couldn't stop thinking and then I realised that it was ok to think as long as I slowly learned to detach from the thoughts. This picture really helps me: imagine a merry-go-round. Our thoughts are like the horses in different shapes, sizes and colours. Our emotions are the music, the lights and the movements of the horses and the merry-go-round. Normally, we are sitting on one of the horses, everything outside the merry-go-round is a blur. The trick is to get off the horse and the merry-go-round and observe it from a few paces away. Just observe, don't judge. That makes it easier to detach and let go of thoughts. Then you look at how helpful or destructive the thought is. Remember: thoughts are just chatter. They are not part of us, they don't define us. A lot of them come from our lizard brain and not from our prefrontal cortex. But we are capable of choosing and changing, otherwise we would not have evolved as a species. I'll think about reading materials and post again.