Hey there, I have/had a very similar problem as yours! I'm not very dry down there, but on my first six months of T, my bleeding had actually gotten much worse than it was before starting HRT. My doctor prescribed me depo, and it really helped me a lot by having less painful times and much MUCH less bleeding. However I would spot randomly, even in the middle of the depo time period. I have recently stopped depo after taking it for two years; at this point since bleeding never completely stopped, and I'd been on T for two and a half years, my doctor suggested we raise my T level and see if that helps. I'm no longer on depo, and my last depo shot expired in January. Since then, I have had no issues, and should I have more, my doctor said we can raise my T dose again.
Unfortunately the only thing I can suggest is discussing it further with your doctor, as well as just giving yourself time. In 3 1/2 months I will have been on T for three years, and it has made me upset on numerous occasions that my body didn't stop bleeding shortly after starting HRT like many do. I haven't seen a lot of people post about this problem online but I can assure you that you aren't the only one!