I would bring the horse back for now, to take the pressure off her and also so that you have kept the stable for whatever horse, her or another that you get. But with the idea that once loaners circumstances are more settled and improved she can loan her again. She might actually once she gets used to the idea be relieved at the cost saving of not having the horsey mouth to feed.
Clearly it's something that has to be done sensitively but it isn't ok for your horse to be at the mercy of week to week overtime when actually that is likely to be needed just for living expenses when going from 2 incomes to one, at least for a while, and ESP when another pony loan is involved.
