Why Is This Ghost Bothering Me?

Let me start by saying we live in a duplex, a pretty nice one might I add. We have lived here for about 5 or 6 years. During those years my mom and older sister have experienced things. My mom has had the feeling of being watched and my sister has woken up to a woman standing in her doorway staring at her. Even my cousins have seen this woman in the kitchen and in the basement. Now one might think that I would be uncomfortable living in my house. But no, I didn't believe it. I mean I had never seen or heard anything. So I didn't really pay attention to the so called "ghost".

Then one night about 3 months ago I was downstairs by myself. All the lights and tv were off. It was like 1:30 am. I was on my laptop. We have this small entryway that leads to the front door. Since the couch I was sitting on faces the entry way I automatically look over into that entry way. And what do I see? A shadow, YES, a shadow. I brush it off at first thinking it's just a normal shadow caused by the lights not being on. But I'm still staring at it. That's when the shadow starts to look three dimensional. I get freaked out and draw my knees up to my breasts but only for a few seconds before I jump and turn on the lights. When I turn on the light I see a woman dressed in white peeking around the corner at me. She's only there for a second then she disappears.

After that experience nothing happens to me. Then about a week ago I am falling asleep in my room. It's dark in my room except for a street light outside my window. For some reason I open my eyes and I see this face staring at me from across the room. I'm just laying there in my bed looking back at this face shocked but still scared. It's stares at me for a minute before it disappears completely. This has happened to me two nights in a row and now I sleep with my tv on. But since last week nothing has really happened to me except for the occasional shadow outside my bedroom door. This ghost keeps bothering me. I don't know if it's singled me out because I didn't believe at first. So today, after seeing another shadow in the hallway outside my door, I decide to taunt it by saying; "If you have something to say to me show yourself to me and say it." I didn't hear anything but I did receive a tap on the shoulder. I am so scared because I don't want it touching me. I don't know what to do, I'm too scared to sleep in my room anymore. In fact I'm too scared to be left in the house by myself. I don't want to be scared but it's hard.