My son of 5 wont eat!

My eldest son of 5 will not eat any cooked food whatsoever. He was a very difficult colicky baby. Solids proved quite difficult as he wouldnt sit still to eat. By two years old he wasnt too bad at eating but never seemed to be very interested in food and would NEVER eat away from our home or with anyone else but me. He had alot of changes at 3, toilet trained, stopped dummy (his choice) and started nursery school. His grew more and more fussy with food. By 4 he was so thin, pale with dark rings under his eyes, had stomach pains, was ratty, whiney and cried over trivial things. Id taken him backwards and forwards to the doctor but this time read about worms on the internet and the doctor agreed. He was de-wormed and we saw an improvement, but after a couple of weeks he was back to not eating much. He would say he was hungry but just eat a little and say he was full up! He woke up 2 or 3 times a night from birth to the age of 4 with nightmares or from hunger. After 4 he started sleeping, but i always made sure he ate something before bed. He loves milk and yoghurt, sometimes cheese. He LOVES all sweets, chocolate and sugary things. By the age of 5 he stopped eating ALL cooked foods, he doesnt eat any meat, chicken, fish or egg. He luckily likes salad, cucumber, tomatoes, carrots, black olives and nuts, which i give him every day, but for dinner every day he will only have dry toast with his salad. I while back i suspected candida in his stomach and have tried various natural anti fungal treatments, I give him probiotics every day and vitamins. He goes through stages of eating ok (still not cooked food)and seeming hungry, and then he goes downhill again and gets moody and ratty and will hardly eats. A couple of weeks ago I gave him 2 does a day of lycopodium 6c but it didnt improve his eating. I then tried