Self Awareness is key.
Even the BSD's here at Elite who deride the mental aspects of trading as worthless work from within that framework, they're simply too arrogant / confident / egotistical to admit or even see it.
Like Bouffant said above....
Psych Books are great. Both Tendler and Douglas IMHO are the goto sources, but that's just what I found helped me come to terms with MY PERSONAL Psychological make up... Everyone is different.
But I guess what I'm trying to say is that the psych books will give you some tools, but you need to be self aware enough to realise what your specific triggers and strengths and weaknesses are and then use the tools say that Douglas gives you in Trading in the Zone in order to get to a place where YOU are able to operate in the markets with the right mental framework...
Trading is a pattern recognition numbers game.... My Fear / Anxiety ceased when I finally got that mental model locked in.