Burning, Itchy Scalp, Excessive Hair Loss After Menopause. Thyroid Normal. Causing Lot Of Stress. Solution?

I am a relatively healthy, post -menopause, 54 year old female, with a burning, itching scalp, and a tremendous amount of hair loss for the past 4 years. This is causing me lots of stress. I do not wash my hair---only once per week, because every time I do, I lose yet another batch of hair. If this seems like I might be exaggerating, let me be clear----my hair was full and thick for years prior to menopause, and the only reason I am not bald now is because I had so much to begin with. I have had a medical checkup, and my thyroid seems to be in the normal range. I eat well and exercise, but no amount of this will take away from the fact that there is hair everywhere except on my head.