Honestly, if you've been thinning gradually over several years, don't seem to shed much and seem to have PCOS-like symptoms, it sounds hormonal and - I hate to say this - it sounds like it may be Androgenetic Alopecia. For your sake, I really hope not! But stress-related hair loss is usually a sudden TE with heavy shedding, from what I know. It sounds to me like you should get a second opinion. I don't have a hormonal imbalance - all my blood tests are normal, and I have no PCOS symptoms that I know of other than irregular periods (which could be caused by high stress and a low body weight). My dermatologist, too, originally commented it was unlikely to be hormonal because I "don't look like someone with a hormone imbalance". I'm thin, don't have a lot of body hair, etc. But when I saw him the other day, he said it was clear I had male pattern baldness, and so although all my hormones are normal, I have an abnormal over-sensitivity to them. It could be that it's the same for you - normal hormones, but your body is over-sensitive to them.