Well, I don't know much about owning or running a barn, but I'll give you my two cents on the situation. She needs to stop taking in animals. I know, it's hard. But there are way too many animals that are being starved, beaten, or abandoned and she just physically, emotionally, or financially take them in. It's fine if you make sure you have feed for your horses but there is a line and if you start putting your house and self into jeopardy over these animals, you're making a mistake.. what if you end up in a box on the side of the road because there were a few sick horses? It's not easy, but if she can get into a more stable position then she can start taking in animals.
It would probably help a ton to sell some of the horses too. Just until she can get enough money to raise money to fix the barn and pastures and start getting a steady income. She needs to practically restart the barn from scratch. You could do a fundraiser, make the barn look "pretty" with good jumps and fences.
But honestly if your trainer is getting tired, I don't think there's much you can do.