Hi, re4nightwing and welcome to Psych Central! Yes, I'm not an expert, but it sounds like she's delusional. Is she harmful to herself or others? If not, then she can't be hospitalized--nor will she be able to be talked out of it.

It's unfortunate that she won't acknowledge she needs help. All I know is to accept her like she is for the time being. Yes, you could question her about things, but be careful or she'll get defensive. And keep a close eye on her to see if she gets harmful. I'm sorry that's happened to her. You are a dear for trying to get her help.