Thank you for all of your kind words in the comments on the last post. It means SO much to me to know that I'm not the only one. To know that there are people who have felt the exact same way and then moved past it is wonderful.
I went out to the barn today. Pony hadn't been worked in two days so lunging was not as smooth as it could have been. Plus, someone had set up ground poles in the 'safe' end of the arena so we had to try and lunge in the scary side. Considering we haven't done anything down there, she did alright. Her circles were small and lopsided (avoiding the scary corner where the goat lives) and she lost focus when the tractor went by, but overall she did okay. At one point she was a bit out of control and pulling and jumping and I just wanted to give up and walk away. But I made myself bring her back down, take a deep exhale and keep trotting.
Our riding was in some ways wonderful (only one little spook and it felt totally manageable) and in some ways not so wonderful. She is now going up instead of forward when I ask for more trot. I used my legs and then followed up with the whip and she bucked and then didn't go forward. I tried sitting back and taking hold of her mane when her head came up so that I felt less like I was going to fall off. But then she'd put her head back down and slow down. She's not in danger of major rearing, it's more she's taking an evasive canter-hop-step. However, I know she needs to believe me when I say go forward. It was pretty frustrating knowing that I'd like to be firm, but my body language is saying "Oh crap!". I kept riding though and made sure to end on a good note.
So, my lesson is tomorrow and I can at least say that I brought my fear back to neutral today. And though it wasn't the bubbling joy of Thursday's lesson, it was at least a place that was neither good nor bad. And, I did it.