You REALLY need CA's book.
It all starts from the moment you approach your horse and how they respect you or disrespect you. ANY small disrespect needs to be addressed immmediately and then you establish yourself as head broodmare or head stallion, and your horse becomes submissive, dropping her head, relaxing, etc.
Your mare is showing you she doesn't see you as the leader from the time you halter her. You are just not paying attention to her signals. Here is the link: Clinton Anderson's Downunder Horsemanship: Establishing Respect and Control for English and Western Riders: Clinton Anderson, Ami Hendrickson: 9781570762840: Amazon.com: Books From the Publisher Native Australian Clinton Anderson offers his training methodology for “real life” horses and their owners. Beginning by stressing the importance of a fundamental understanding of horse psychology and “why they do what they do,” the author introduces readers to safe and specific ways to approach training or behavioral problems, then guides them through basic groundwork and under–saddle exercises. Throughout, the book features two “real horses” with “real riders” and “real problems,” their experiences with Downunder Horsemanship, and how it improved confidence, established respect, and provided “real solutions” for all involved. Clinton Anderson trains, tours, and conducts clinics across the United States. He stars in a weekly satellite television program called “Downunder Horsemanship TV,” where he works with untrained and “problem” horses. He (WAS) based in Sterling, Illinois.
Now, CA is in Texas. I have an original copy, but it has since been updated.