Hair loss in females is a little more complicated than that of males. Several factors can contribute to hair loss/thinning such as hormones, the thyroid, underlying illness including auto-immune conditions or it may just be genetic hair loss. In your case, you would need an in-person evaluation and possible biopsy to get a proper diagnosis as to what is causing your hair loss/receding hairline. There are many great treatments and solutions that work wonders for women however, I wouldn't waste your time and money on these until you see a reputable physician who specializes in hair restoration. If it is in fact treatable, I highly suggest starting a haircare regimen also known as 'medical management' as soon as possible because treatments are most effective in the earlier stages. Treatments for women include PRP Therapy, Low-Level laser therapy (Capillus), a hair loss prevention shampoo such as GroMD or Nizoral, GroMD's Follicle Activator Spray, Rogaine for Women, and Scalp Micropigmentation.