Sometimes trying to explain something to an elderly person is like beating your head against a brick wall.
No matter what you present as an argument they counter it with the same statement or opinion.
This is the problem I have been facing lately. After college I moved in with my grandmother to save money while I paid my student loans and looked for a job. This was helpful to her as well because I could run errands and help with household chores. As I was looking for a job I kept seeing ads for a local cannabis farm that was hiring workers. I figured I could do this part time and earn a bit of money to help pay down my loans faster. They were starting people out at an above minimum wage and I wanted to look into it. Well, I made the mistake of mentioning this to my grandmother and I might as well have told her I was going to rob a bank. She started spouting about me being a drug dealer and that she would have no part of it in her home. I tried to explain that it was a legal business and that the marijuana farm where I would be working only grew cannabis for medical use. I also tried to explain the difference between what you buy on the street corner and what is available to individuals to help with symptoms associated with their conditions. Again, she said that she would not condone anything that had to do with growing pot and that I would have to move out if I took the job.