Afraid to sleep.

As I wright this I am in costa rica, in my grandmothers house. Now I know the source of my problem. My problem is that 1 year ago I was told that my cousin and one of my grandmothers friends got robbed by men who held that at gunpoint in their own homes. I've always had problems sleeping in any room alone here while I visit my grandmother. I don't know what to do... I've tried many suggestions such as leaving a night light on, thinking good thoughts and everything else in the book. I basically have a panic attack almost any time I hear a sound And I'm alone at night. This fear is becoming extremely irrational and I don't know what to do.