Explain to her that compounds are money pits and loose their value quickly. On the other hand a well cared for used recurve or longbow will hold it's value much better over time.
It's a hypothetical situation but consider what your compound will be worth in ten years compared to what a recurve that you bought with the funds raised by selling said compound right now would be worth...the compound will have little if any value, the recurve would probably not loose any value at all. Sell the compound...stop the depreciation.
Mechanical bows are great, I have one, mainly because at this point it's not worth selling it since I won't get much for it. It still shoots well so it's not that big a deal, but it's far from my only bow. I'm a stickbow guy at heart and am fortunate to have several nice custom recurves. Most were bought used and I'm confident I could sell them for the same amount I paid for them.