She cannot see the horse and burro from the dry lot.
She is no longer crying for the horse.
The pony is eating every scrap of every single thing she gets.
The horse has a burro with her in the pasture, so she's not lonely at all. She has the burro, which, while not her favorite companion, is sufficient as a companion nonetheless. And he is 'lower' than the hard keeper horse, so she gets all the hay and grass she needs 24/7. The horse is eating fine without the pony.
Pony definitely paces, though. Although, when there's food, nothing else matters to her. She would leave the others to eat at any moment. However, because of this she does do a lot of pacing at times when she's consumed all her hay. She has 2 tiny hole hay nets, a salt lick, a few toys (never plays with them), water, shade and a big area. But I do think herd animals should be able to be with a buddy.
We are in a horrendous drought, so the area I would make as a pen doesn't have any grass. Plus, she'd eat whatever was there in 2 days and there would be nothing. She is an eater. Also, it has trees for shade. But I DO worry she would blow through the tape and end up in the pen.
So ... do you think the sheep is the way to go?
I wish I had the ability to split up my piggy from my hard-keeper. If I were in your shoes, I would be looking at the pacing pony saying 'thank goodness, that weight will finally be off her'.
Would you be able to put the burro in with the pony instead? How would the hard-keeper do alone in his pasture?
Have you tried a grazing muzzle with the pony? Is she able to be on grass at all? I would be inclined to keep her separated if she limits how much forage the hard keeper gets.
I would be inclined to get more small hole hay nets, and spread the bags throughout her dry lot. If she is eating them like crazy still, double-net them.
If you were to separate her within the pasture, how big is the pasture? Would she get upset when the hard-keeper goes to the far end of the pasture? She may just be as upset being in the pasture, separated from them, as she is now.