What do you do with a 78 year old woman who has Lewy Body Dementia and sees people at night. Every night she claims these people get in bed with her and won't leave her alone and they hang out in her room she carries on a conversation with these imginary people but they never talk back to her cause there is no one there and she gets mad when I tell her I don't see them so she thinks I'm calling her a liar please help me out.
Contradicting someone with dementia is not usually productive and, as you've discovered, can agitate the person.
Ask her to talk about the hallucinations. Who or what does she see? Can she describe what they're doing?
To her, these hallucinations are very real and how scary it must be to have people climb in bed with her and hang around her room. It's okay if you don't see them. She does. Try telling her that you believe her. And if these hallucinations are threatening to her instead of telling her there's nothing to worry about try telling the hallucinations to leave her room and leave her alone and let her get some sleep.
If this doesn't work talk to her doctor about medication.