I have an issue. It's been an issue for almost a year now. I've been dating my current boyfriend for a few years. We started dating in high school. We're great together and his dad's side of the family is great. His mom's not so much, nasty divorce and she chose his younger brother over him so of course she doesn't like me either which I'm pretty okay with. However, over a year ago my step sister who is the same age as me, went through a big break up with her long term boyfriend. It was messy but she still dated other people and even cheated on two of them. The last one she cheated on was with my boyfriend's little brother. I have been against them dating since it started and so has my boyfriend. And at first no one really understood why but now it's kind of coming into the light. She's graduated high school so she's "legal" he's still in high school for a few years. They've been a bad influence on each other for months now (toxic as in fighting over the phone every night over someone saying something and the other taking it the wrong way, possessive/controlling too). The dad's side of the family doesn't like her and has said that if they have sex and they find out she's being put on the sex offender list which would obviously cause family problems. However, the mom's side loves her and lets them do WHATEVER they want while the dad's doesn't for obvious reasons. She also likes to tell me things like "I dont know how you can stand your boyfriend not having a good relationship with his mom. I guess I'm just dating the better brother." And she has tried rubbing it in my face that he got her a promise ring and I don't have one, but it doesn't bother me but she acts like she wants it to bother me. (She got this ring ONE MONTH into dating him.) And she doesn't let him talk to me. As in whenever she's not around, her boyfriend talks to me constantly and it's just conversations about his job, nothing flirtatious at all, but when she's around she answers questions for him and doesn't let him speak. We used to be really close, but now we're obviously not. And I dont know what to do because my family knows nothing about everything going on. She even had him block me from his Snapchat because I was with my boyfriend's family one day and they took a snap of being somewhere his dad told them they weren't allowed (lied about where they were going) and they saw it and obviously got mad. They've threatened to break them up and everything and now we're very sure they're having sex because his uncle found a used condom beside of the brother's car. So it's all about to blow up. And my relationship is already being ruined by everything else with her and if something major happens I don't know what to do. I really need advice. I can't talk to her or him about it because I've already tried and both have lied directly to my face (I caught them doing some touching in BROAD DAYLIGHT in a parking lot and called them out on it and they still lied to my face). I really need some advice. I can't tell our parents because they believe her over me with everything (she's the one that goes to church every Sunday and makes the better grades and I'm not). Really need some advice or someone to talk to about this.e