I was doing 3 rides/week in good footing: a dressage lesson, dressage schooling in a nice arena, and a short trail ride over soft dirt in the woods. She was holding up to that well, but the vet wants her on rest again. He agreed I could hand walk or lunge her, so I may pony her down the trail with my other horse. I'll just have to be careful to only use trails with good footing and not push her to walk faster than is comfortable.
Thanks for the advice about shoes. I'm hoping to be able to work WITH the vet to find something we can agree on. I think a pour in pad sounds like it would help with her comfort and support. I've got some more research to do it looks like. Nails were bad for her previously, but we haven't tried shoes at all in a long time.
Also, I heard back on the thyroid panel and it was normal, so the vet thinks she is just IR. I must need to look at her diet a little more closely.