I'm scared I'm slowly going insane

Hi, so, I'm sixteen, and it feels like I've been slowly going crazy all my life. since I can remember I've been afraid that there's stuff out there that can't be seen, or well, that can't be seen by everyone else, I see things, shadows, and figures, shit like that, I've seen them all my life, and at first when I told my parents they said it wasn't real, so I just convinced myself it was my imagination for a few years, until I was ten, that's when we moved to a new house, and every time I went up the stairs I could swear I was seeing a face on the window, instead of doing what a normal parent would do, my mom started telling me it was real, she was getting into spiritual stuff like reiki and I don't know what else, so yeah, she started saying it was real and it terrified me. It's been six years of her telling me I have a gift and what I see is real, and I'm scared I can't tell when it's real and when it's not, we've moved two more times, and in both houses I've seen things that still haunt my nightmares. I actually can't function normally anymore, I can't sleep well, I can't shower, I can't do anything because I'm afraid they're here with me, I'm starting to believe her, and I'm scared if I talk about them they'll get mad, I try to reason with myself, but if you've ever been in my situation you'll know it's not easy. I don't have any friends I can talk to, and I can't ask my family for help because my mom believes it's real and I'm no contact with my dad. I'm sorry if this is badly written, it's two am, english is not my first language and I'm freaking out.