I appreciate the advice everyone.
That said the problem is a little deeper than that. It's not actually a tying issue. This week I didn't tie her, I had a friend hold her while I tacked up. She still went up/pulled back. My friend gave her slack on the rope and the mare went down. I'm lucky she didn't injure herself. I don't really understand. Two vets, a saddle fitter and two instructors say there's nothing wrong with her back or her tack. Sometimes she pulls WHILE the saddle is being put on, sometimes when it is already on, and sometimes when it hasn't even been brought out of the house yet. Oh and for several weeks she doesn't pull at all. She also goes back when I'm mounting, but only sometimes.
At the moment I'm just making her work HARD whenever she does it, but I'm a bit perplexed. It's a really new thing and I have NO idea what brought it on
So yeah, tying isn't actually the key issue really.
~The most important lesson my horse ever taught me is how much I have left to learn~