Is it normal to have obsessive thoughts about being killed?

is it normal to constantly feel like someone is out to kill me and wants to hurt me and my family? im a 19 year old female from the UK and almost every single day i live in fear that someone wants to hurt me, my mom and sister. constantly having obsessive thoughts like this keeps me up at night. it’s been like this for years but has been getting worse over the past few months or so. i feel like i can’t talk to anyone about it, how do i tell someone that i think someone is going to kill us? ive been in and out of therapy for almost 9 years now but haven’t really told any of my therapists about it because im embarrassed, i havent told my family either for the same reason