I do agree with your point and appreciate your comment. We all need to see more comments that help explain why the homeless do act the way they do. One thing I do not agree with is that basically you are saying "homeless people need therapy and drugs to help them".
People don't need drugs or therapy in most situations. Rebuilding neural pathways or synaptic connections require only a reduction in stresses that cause as you call it "the fight or flight". Once a person is in a non threatening environment for a period of time the person will return to whatever was normal before the stress was introduced.