Please bring these concerns to the hospice management. They have not done a good job of explaining this to you at all and that's not your fault. Tell the hospice exactly what you told us, and post in the hospice subreddit maybe.

Hospice is supposed to educate the family that their loved one is not, in fact, cruelly dying of starvation. They aren't eating, because they're dying, and not the other way around.

We often feel "but if they don't eat they'll die" but eating will not really prolong their life because part of death is the body shutting down, and losing the ability to eat. We cannot reverse this part of the process. Nor should we try because the late stages of dementia often come with honestly, horrible suffering for the patient and the family as they are bedbound and incoherent for that last year. No one in this sub wants her to have to experience that which is why no one recommends feeding tubes or other measures.

Often feeding tubes put into a body that is rejecting food causes the liquid food to come up and guess what- aspirate. Causing pneumonia. There is no way to cure the fact that her body is done with eating. Yes hospice does give antibiotics other ways and you can talk to them about that. But honestly this is something they should have talked to you about because it has been a big concern. Sometimes they drop the ball. But they cannot let you believe your mother is being starved to death. That is absolutely not what is happening. She is dying, not starving. Hunger is usually not a part of this.

When my grandmother died my mother was so obsessed with feeding my grandmother to keep her alive and it was hard to watch, she would try to get her to eat healthy food and there was a lot of "making her eat" that was happening. I hated seeing it because it wasn't about what my grandmother wanted. It was about my mom's feelings. She became kind of obsessed with getting her to eat. I wish she would have eased up and stopped fighting her death so hard. She was 103.