First: Does your saddle and stuff fit for sure? She could be associating you with pain on the ground and fighting with you under saddle because of the pain.
Second: Could you be nervous at all about working with her?
I once knew a mare who would sense when a person was nervous and totally exploit that to get her own way. She would buck and kick and run off with and bite people etc until the people always ended up leaving her alone which was what she wanted.
I finally got through to her by turning my fear into anger towards her. I wasn't abusive but I just got to the point where I knew I had to work with her but I was scared as heck so I got mad as heck. I would smack her really hard when she'd try to bite me and I generally let my frustration at the world come out as I worked with her. I never beat her or anything I just didn't let her get away with anything at all. I would carry a crop (one with a popper thingy so it made a loud noise and didn't really hurt) when riding her and smack her when she acted like she was going to kick or be a butt.
And you know what? After a month or so of being completely harshly tough with her she finally came around and stopped fighting with me. She still bossed the other horses around in the field but she knew I was the big boss and that she needed to be good for me. Once she realize that, she was the best trail horse ever. She'd do anything you asked whether it was jump a 3 foot log, she also jumped an atleast 5 1/2 foot fence before..but that's a different story (she was around 12.2 hh! and we were "making a trail" so I had no idea about the log) or give small children pony rides.
All I had to do was show her that I was not afraid, no matter how scared I really was, and she would be fine.
Good luck! I'd also advise that you stick with the normal snaffle, stronger bits aren't a good behavior problem fix. =)
Edit: Also, are you sure of her level of training? If she was started later, like say at age 3 1/2, she may have never really experienced trotting/loping or anything much more than a walk yet, which could cause her issues under saddle and could cause her to dislike you because she's confused as to what you want...
Fabio - 13 year old Arabian/Lipizzan gelding
Hazel - 14 year old Angora goat
Atticus - 4 year old LaMancha/Alpine cross goat
Rest peacefully, Lacey.
Last edited by Wallaby; 06-09-2009 at 10:17 PM.