I do halter with all my youngsters too even stallions. First lose the treats. Next Appys are extremely curious but more important SMART. It shouldn't take long to teach her to stand. Check your body position while she is on the lead stand up straight. The more upright and puffed in the chest the more respect you'll get. Slump, hunched shoulders or looking down your horse will move around. Teach a word I use "stand or stand up" and can have them stop mid pasture and wait. Next decide where you want her, stand her up tell her stand and then either use your show stance or hang out doesn't matter[start in show stance] I use a chain over nose,but its not neccesary. When she moves a small jerk and put her feet EXACTLY where they were. The feet is what you are working with, stopping the treats will stop her pushiness and creeping. Wait 15 seconds move off any direction start over, increase your time length. Multiple training sessions will work better than one long one. Turning out/ in great training time. Good luck