Someone with whom I used to be friends keeps taunting me when she knows that I cannot do anything about it as no-one believes me. She keeps coming to my window at night and making fun of me but then hides when I try and shout at her to stop as she doesn't want people to know that she's there, and then when I open my window and start screaming outside at 3am to make her go away, she always stays hidden to make me look like an idiot.
When I was a really young child I used to go for walks with her and my family and there was this wishing well in someone's front garden where we'd always make a wish. Yesterday evening I went for a walk on my own and found the house where I used to go as a young child and found the wishing well in the front garden and started clicking my heels and saying, 'there's no place like home, there's no place like home'. The owners came to the bedroom window however and shouted at me to '**** off' and I started to cry. She always comes to me and reminds me of it, laughing but when I try to challenge her she always hides and no-one believes me. She keeps hiding my stuff and putting it back before I can prove that she's taken it. The one time, I put a trinket on a coffee table in the lounge as I knew she'd take it as soon as my back was turned. I then spent the night hiding behind the curtains to catch her in the act, but she knew I was there and so every time I came out of hiding she quickly hid so that I couldn't prove it.
I'm crying as I'm writing this because I'm at my wit's end and when I try to tell people about it, they just think I'm going mad and don't want to help me.
What can I do?