Trust issues

In the past I have been through a lot, Friends betrayal, my family dont trust me, Exs who betrayed me, one of my family members tried to #.. so anyway I will fight and try to comfort myself by myself bcs I dont feel trusting anyone. so now the issue is me and my sister relationship is getting worse. Its start when I got engaged in february. my sister is married she is younger than me. since I got engaged she always try to make a bad picture of my fiancé, I once found my fiancés picture in her phone, she wrote anonymously in a web complaining about her life with her husband, shes most in our house than hers and her husbands house, the problem get worst when yesterday I planned to play Sims with her, make characters and build a house. so she made a character that almost look like my fiancé then she use my full fiancé name to name that character she made. then she made another character which is going to be the wife of that character and she put her name. I was in shock I told her were not going to use real names. she didnt even say oh dont get me wrong she act normal and thats what scares me. I feel unsecured around her. Its all weird. I dont think that is jealousy I think its gross. And I cannot talk to anyone about it specially my family members. Give me your thoughts. Is there any advice?