My focus was the other two posters saying herbal tea wouldn't ruin the fast. Those kinds of comments create a snowball effect which creates other posts confusing what Water Fasting is.
I am not sure how much psychological healing can be done by not eating during a fast. There is a huge difference controlling ones urges while fasting verses eating in moderation. Fasting will encourage you to make better food choices but it wont teach you how to face your 'psychologically issues' when you start eating again. You still have to practice control when you begin to eat again. No one is successful at fasting till they learn how to break a fast and move forward with mindful choices.