I assume you have had a thyroid check? That's the first thing to start with. Then perhaps see a natural-health specialist. Talk to your regular doctor, of course.
Daggone! I'm sure this is hard! Hair does thin due to hormones which can be caused by things like changes once you've had a baby (my hair got really thick and lovely during pregnancy and then after I was finished nursing, thinned out to less than I had before pregnancy-- man, was I irritated about that). Thyroid can also thin out hair.
But if you are almost bald, I'm thinking you've got alopecia? What does your doctor say? They DO have treatments for that. Alopecia is an autoimmune disorder and they prescribe medication for it. They treat the autoimmune disorder and then add hair regrowth treatments that are meant to stimulate hair follicles. This is something you'd need to work with your doctor on.
I also, as another option, have a niece with an anxiety disorder that causes her to pull out her hair. She's gotten to the point where she is essentially bald. Sad. She's in her late 20's and a beautiful, successful woman. But has this uncontrollable urge. She invested with a specialist to create hair pieces for her. It was expensive but I'm telling you, you would NEVER know she wore hair pieces. It looks completely natural and not like a wig on her head. I believe it was around 2000 dollars but for her, so worth it. She has hair! This is something your doctor could put you in touch with or the society around this disorder. It's called trichotillomania and those who have it often seek out professionals to create hair for them.
Hope this helps. Stay in touch!!