If she doesn't like it, do it more. It's not about her being 'used to' it, it's about her accepting it. If she tries to buck or throws her head, keep that leg on until she gives up and then ride on like nothing happened.
Yep, exactly. I've had two horses that would run INTO my leg, not just resist it. One of them would run into my leg so much so that she'd crush it against a fence, or fall over her own feet. My leg did NOT move on that horse, she could buck, take off and carry on like an idiot all she liked, but my leg was not going to budge until she gave up the carry on and accepted my leg, if she went to buck, she got a dressage whip across the backside. Took 2 rides to get it out of her and she never did it again.
If you take your leg off when she gives you that negative behaviour, all you're doing is re enforcing that bucking to the leg is a comfortable thing to do. She doesn't hate leg pressure, she dislikes the work that comes out of it. DO NOT give away your leg until she gives in, make it uncomfortable as hell for her to go stupid to your leg. As soon as she relaxes and gives to it, take the pressure off and just work her with your leg lightly sitting on her sides. Then ask again, if she crakcs up PRESSURE ON, she settles down and moves off the leg, pressure off. Horses are VERY simple creatures!!
I'd recomend working on turn on the forehand and leg yield in walk. Move her off your inside leg anywhere and everywhere. When you go around a corner, ask her to move her hind quarters away from your leg, on a circle, make her do a turn on the forehand. This will get her cued into your leg aids, and you WILL get a response when you start asking her to come under herself or move up a gait in higher paces.