I think that it is unlikely that she's had a stroke. However, it is possible that she was bit or stung by an insect, but that would not cause the long term weight loss. Her signs could also be in response to dental disease or an ear
I recommend having her evaluated by your regular vet. I would start with a physical exam and some current blood work. She may need sedation for a thorough oral exam. Hopefully, this will be enough to give us a diagnosis and begin as treatment plan.
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