If she's a typical sensitive to seat TB, it sounds like you need to go back and teach her a proper half halt so you can rebalance her as often as necessary. Sounds like she's getting all strung out. Since she is the forward type, the half halt will also either fix, if she's already heavy on the reins, or else prevent her from becoming heavy up front. Half halts are pretty each to teach to TB's since they feel every little thing. Like Kayty said, a good dressage instructor can best help you. If you're a self starter, there are plenty of good suggestions on the internet. Maybe try a few and see what gets the best response from your horse. Just remember, whatever you choose as your cue, be consistent and reward every try.
You just have to see your distance...you don't have to like it.