Hello yuvalyar: This appears to be your first post here on PC. So... welcome to Psych Central.

We here on PC cannot offer mental health diagnoses. Plus I'm not a mental health professional. So I can't suggest what may be going on with the person you describe. However based on what you wrote, whatever her diagnosis might be, it sounds as though she may be struggling with delusions. So here are links to 8 articles, from Psych Central's archives, on that subject plus 1 on how to persuade a loved one to seek professional help & 1 on how to help a loved one who is in denial:

10 Things You Should Know About Delusions | Caregivers, Family & Friends

10 Things You Should Do With Someone Who Suffers Delusions | Caregivers, Family & Friends

8 Ways To Cope With Someone Who Has Delusions | Caregivers, Family & Friends

Delusional Disorder: 8 Ways To Communicate Without Fighting | Caregivers, Family & Friends

Part 1: Getting Through To Delusional Beliefs | Caregivers, Family & Friends

https://blogs.psychcentral.com/careg...dium=popular17

https://blogs.psychcentral.com/careg...hout-fighting/

https://blogs.psychcentral.com/careg...dium=popular17

https://psychcentral.com/blog/how-to...dium=popular17

https://psychcentral.com/blog/11-way...-denial/?all=1

I hope you find PC to be of benefit.