Should I tell my roommate about firearms in the house?

I have no idea how to start this but I'll just get into it. I tried to google and see if anyone else was in this scenario. I have a roommate who had a suicide attempt. I am a woman who works in the evening and I was thinking about looking into arming myself to protect my home. There have been a lot of scams going on locally of men trying to convince people to open their doors (having a child scream from outside, pretending to be some utility company, and some full on trying to break down doors, etc.) I've been thinking about doing some research to keep a gun in my home. I would keep it in a safe under my bed of course. My roommate is almost never in my room and I would start locking the house if I knew they would be home. The question I have: should I even tell this roommate about my choice to arm myself? If the circumstances were different I'd want to inform my housemates of my decision, but I worry telling this roommate as I think it would do more harm than good. What do y'all think?