Diet alone can help get candida symptoms under control, and this may be enough to help clear your mind and give you some relief. Following the other steps of the protocol (antifungals, pre/probiotics, curing nutrient deficiencies etc) is what should eventually provide the cure, which will require you to deal with your stress problem.
Depending how poor your diet is now, switching to a wholefoods diet that doesn’t force you to snack every 2-hours to keep your blood sugar stable might help your emotional problems too. There are many links between nutrition and stress/depression.
I agree with Thomas’ recommendation of ACT. There’s another book called The Happiness Trap that’s quite good, and Full Catastrophe Living helped me resolve some anger/stress issues. I believe good nutrition, exercise and a good approach to the psychological side of stress/depression is enough to help most people overcome it. For people with serious issues that are hard to deal with, maybe someone to guide you would be helpful.