I wasn't aware that you can lose actual body hair with Alopecia. I thought you only lost hair in a particular area of the head eg: crown.
I was going to ask whether you had done further testing, but it appears you have. Most females who are prone to Alopecia, from what i have been told, see signs of it during/after menopause. If you aren't even going through menopause and you have Alopecia it could be an early onset of Alopecia due to another contributing factor such as anemia or long term low iron stores or thyroid issues.
The worst thing about some doctors and tests is that they can run these tests and if you fall 'within the range', they simply say you are OK. This gets told to a lot of pateints when in fact for certain things if your test shows you being at eg: lower end of the range, you can still suffer symptoms.
I know my situation is different to yours, but as an example, i eventually lost about 2/3rds of my hair and no doctor could help me. They would run tests and say my tests were ok. Then i discovered this board and picked up a few ideas and then when shopping for the right doctor for me. I eventually found him and he agrees that mere tests were NOT ok. My iron stores were too low, which definitely were contributing to my hair loss. My thyroid wasn't at the level were i required med's, but was at a stage where i would be experiencing side effects. I was also found to be very low in certain vitamins/minerals.
The thing is, lets say you definitely have Alopecia, but do you have an extremely strong case of it where you lose body hair/eyebrows/the lot (which again, i've never heard of, but not to say it can't happen), but what if some other illness is contributing to the Alopecia and you have lost more hair than you normally would from a simple case of Alopecia?
At least you are trying to find answers by visiting a healthboard, but i would shop around for a doctor who has some knowledge and empathy and a willingness to help. I wish i had done all this 7 years ago when my problem started, but stupidly i believed my family doctor back then, who also sent me to an equally stupid dermatologist who also said everything is OK, when in fact i was later to learn that NOT ALL dermatologists are qualified to deal with actual hair loss.
Don't give up, even if your condition can't be reversed 100%, it might be able to be reversed by a certain percentage. All the best and let us know how you get on