You can't sell her, and if she's not likely to have a sound existence, euthing is a valid option. If, however, you can afford a few months to feed her up and the vet bills, it may be worth giving her a chance. A tooth float and chiro adjustments aren't that expensive, and you may be surprised how well she does. If she is still struggling at that point, then you know you tried and it didn't work.

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