11 isn't really that old, I have several that are in their early teens and still having kits.
All of suddent things deteriorated quickly and now she completely stopped eating and struggling to stand up. I looked at her poops and they look ok and continues to poop a little though it's about half the size of normal (seems like no digestive track blockage).
It does sound like she is heading for dehydration or already there. Once the poops stop, she's in real trouble and from what you are describing she is headed in that direction.
Not eating and not drinking is a bad sign ... this by it's self can contribute to impacted bowels. Do you know how to force feed her?
If you do not want to do that, you could put some Ocean Spray Cranberry Juice 1/2 and 1/2 with water to encourage her to drink.
If she does not eat or drink soon, she will be very close to death.
Are there any other chins that are sick at this time? If not, watch for it ... especially if she is still in the same room with other chins.
It will have to be up to you to decide what her fate will be. If you want to allow her to go naturally, you may want to stay with her and hold her ... I always do with mine ... until the very end ... but , some people prefer not to do so.
If she has a gagemate, I would not leave her and the cagemate together ... this can be pretty rough on one to see it's mate die.
Jo Ann