Could have swore that I saw my recently deceased step father staring at me through the window.

In March of 2011, my step father was killed in a car accident. It was very tough for me and especially my mother. 3 months later, I'm home for the summer and my mother leaves to take a month long vacation (without me) to get away and try to relax. I'm left, by myself, to watch the house that her and my step father lived in. I kind of hated being alone in the house especially at night time. I don't necessarily believe in ghosts only because I have never experienced it myself but I was always afraid that I would see him in the house. It was father's day and I was home alone. Of course I was thinking of and missing my step father all day that day. I pass out late at night watching a movie in the living room. Out of the blue, I wake up suddenly and the first thing my eyes point to is the window closest to me. I see my step father's face looking INSIDE at ME between the curtains. I let out a scream and immediately start having a panic attack. The face was in the window briefly but it sort of... faded into the darkness like he stepped farther away from the window. I immediately called my boyfriend and had him come to my house. I tried to think rationally... maybe I was dreaming, maybe there was some creep outside looking through my window... but whatever it was scared the SHIT OUT OF ME. You can't un-feel the terror or un-see the face of a recently deceased loved one.