Is there any chance she might have Cushing's disease?
Cushings Disease in Syrian Hamsters - Hamster Central WIKI
This article may help but there is no cure.
If you feel in your heart that she has had enough and is telling you she needs help on her next journey then your decision will be the right one. Made from love it is always right so never regret a this choice. She is trusting you to listen to her whisper when she is ready.
I hope you can make a decision that lies easy on your heart.