Please help. Is this a sign of dementia or something else. He is making her very uncomfortable and I just learned about this. We do know that he has an obsessive crush on one of my brothers friends that is 42. How do I handle this situation. He lives with us as does my daughter. I feel that he needs to go to the doctor and be evaluated. While he gets around ok he can't cook, pay bills, remember to take proper meds etc. Any thoughts and suggestions will be welcome.