I'm having friend problems.

I have a friend, elaine that I was really close to, and I mean really close - we hung around everynight and we went walking everywhere, wedone everything together but we have been drifting apart a lot recently. She would rather go in for my neighbour rather than me, she started smoking and drinking and she got a boyfriend. She takes her boyfriends side against everyone else’s. I have done nothing wrong to make him hate me yet he does. He calls me names and I try to tell elaine but she never believes me. She didn’t even tell me she had a boyfriend, I got told off my sister that was friends with my neighbour, sasha (elaine told sasha) - they hang around all he time now and I ask elaine why she never comes to my house anymore and it’s not like I can go to her house because im not alloud to go to her house. Her parents hate me because elaines brother said to her parents that I took drugs, was rascist and smoked and has slept with half the town. He told his parents when I was about eleven and they believed him. I have never took drugs, I dont smoke and I don’t go around sleeping with everyone! Everythinghe said are lies and he knows it. It’s not like elaine has any reason not to come tomy house because she goes to sasha’s house all the time. Elaine has been hanging around with people that smoke weed and I confronted elaine and said they re bad people, she said she nows they are bad people and she said she would keep her guard up. Then she started drinking and then started smoking weed. She ha changed and she has a whole big attitude all of a sudden. Should I just forget about her? She says im jealous because she has someone that loves her and that I can’t get that. This is making me go crazy! I miss elaine, I want the old elaine back, I want us to hang arond like we used to. Elaines boyfriend and sasha went o my house about 10 minutes ago (sasha doesn’t like my sister anymore) and I answered the door and I said hi and hey asked if my sistr was coming outside. I told my mum that I dont want my siser hanging around with them and my mum said that she wasnt alloud out but then my sister jut walked out the house. I don’t even know why they would ask my sister if she is coming out, all I can thnk of is that they want to change her into one of them. I’m in a really crappy upset mood after that. I’m so confused. I want everyone how it used to be. I feel like just sitting in my room all day crying,im crying right now. I’m just sick of it all! What do I do? Sorry about the spelling, this kyboard is crap t_t