I am not a doctor, and I don't pretend to be. I'm not medically trained in any way (unless you count AS level biology..and even then I didn't do too well ) but I do still want to share my experience and advice in dealing with anxiety and depression. You don't have to agree with everything I say and you don't have to follow my advice. The truth is, everybody is different and some things work for some people and not for others. One of the main things about conquering any anxiety is to find out what works best for you personally. I've tried hypnotherapy, dietitians, nutritionists (apparently different from dietitians), CBT, psychotherapy, and EMDR. I find that a combination of all these things helps me best. But there are also elements of some of these therapies that I don't think work very well and I wouldn't particularly advise.
I'm from North London originally and I had quite a normal infanthood. When I was a young child though, at about the age of 7 or 8, I had several close friends who lost their parents very suddenly. One was my best friend and her father died in his sleep, another was my "second" best friend (anyone else used to do the whole first, second and third best friends when they were kids? haha) and her father also died of a sudden illness. I think this made me feel unsafe and unable to help them. I developed separation anxiety towards my parents and I didn't go to school for a while. I have always been a thoughtful person and I think I let my thoughts run away with me and nobody really knew how to help me.