my mind is going mad

Why is it I remember bits and pieces of things but not everything it's like someone stole parts of my memories. Why is it that over time I can't distinguish what really happened or was it just a dream? Why does the sands of time take away history. How am I supposed to know the difference between what's true or what's a lie? Has my mind gone mad and made up stuff that's not even happened. I feel like I've been here before like Ive said this before and I'm just repeating myself over and over again. I just want to shut off my mind. Will anyone ever hear me?