Before u read anything else u have to know that Yes i understand its her own life and its her decisions and she should live her life they way SHE wants too. But im really worried about her position.

Here’s the beginning.
My best friend used to be super girlie and I’m not sure when but a couple of years ago she started liking anime and anime is ok but she is completely sure that the characters exist. With every video game she plays she tries to tell me some story about the characters and how she met them. Then one time she was so sad because her “best friends” Edward and Alphonse Elric from Full Metal Alchemist didn’t come her her house. Then another time she was completely sure about seeing Matt Jeeves from Death Note in her bed with his goggles on and he had bed head and she hadn’t seen him the night before. She tells these stories to all of us and not all of us believe her except and Yani believes her because she trusts our friend isn’t lying. She also thinks Gara from Naruto is in love with her and he “stalks” her she said he gave her a rose and her front yard is full of roses she had a little bouquet of flowers and she had said that he had given them to her and she had a bush full of them I’ve never seen him near her backyard and I’ve gone to her house many times. I don’t know what to do every time i tell her i don’t belive her she gets all mad at me and she says she’s telling the truth. Please help me i don’t know if i should leave it alone or stage an intervension. I think shes getting these habits from her two older brothers because they taught her about anime and manga and i think the only solution her parents could find besides therapy and a phyciatrist is that she goes to boarding school next year in BOSTON and we live firken Mc Allen so its a long way. The only thing i can get from her moving there is that she wont be with her brothers and they wont give her more ideas but i really don’t know shes my best friend and i want her to stop being like this because its unheathly i mean she thinks theres a naruto academy and a ninja academy i looked those online THEY’RE MMORPG GAMES she said shes a lvl 4 ninjia but idk shes really obbessed and i want to her becaue shes my best friend i don’t think that whats happening to her is healthy for a girl our age. Don’t say it’s a phase because its been gong on for years it’s been to long for it to be a phase. Once again i know its her life and she should be able to live it anyway she wants to but all of us are worried about her we don’t want her to get into a sitiuation where she’ll use her “ninjia training” and end up hurting herself or even worse dieing i’m not making this dramatic or blown outta porportion. She’s like a sister to me and i luv her alot (as a friend). She’s a wonderful girl to be around and her parents are wonderfully nice people so the only way she could have gone like this is from her two older brothers (no surprise there) i just want her to see that anime people dont exist and games are just games. Please help me.
Earlier today i had a foward and i sent it to her and it was one of those were u put the name of ur crush and i had put mine and she had txted me back saying this “I DONT LIKE OR LOVE NO ONE” and i had put “girl chill u dont have to yell” and she had claimed that she wasnt yelling she was whining and wen i told her that she is lucky she doesnt like anyone anymore and y she is lucky she got all pissed off and ignored it because if she read it shell break ANOTHER dice box and shell be sad. She also lies alots and thinks she has to be the best at everything wich im guessing is another learned trait from her older brothers but i just dont know how to get her to stop being like this she was like this before but it increased after a rejection. she had thought that after confessing to the guy she liked she wudnt care about wat he said well she was wrong she was soo mad that she took it out on everybody else could this be a trigger to her problems were she thinks she has to to be the best?