Constant sense of dread

I'm living with this underlying sense of dread all the time as if something terrible is about to happen. I'm always worrying about something bad happening to my loved ones in particular, and whenever I say goodbye to one of them I have an awful feeling as though it might be the last time I see them. I'm just always waiting for disaster to strike and it's having a really negative effect on my life. I guess it's my brain realising how unpredictable the world is and being unable to accept it. I was just wondering if anyone else here deals with this and if anyone has found a way to ease the stress.