This is my first time posting, so I guess this is an intro and first rant.

My fiancé and I met in late 2015. We hit it off very quickly and I moved three hours away from my hometown to live with him. SD expressed reservations when he first broke the news I would be moving in, saying something about it being like one of those evil step-mother Disney movies. In the first year or so, there was jealousy and a competitive spirit between us; but it has begun to improve. A little.

We've hit a few snags with the BM. I'll detail the most profound ones below:

The summer before my fiancé and I even met, he allowed his ex-wife to move in for a few months. He says this was because she was pregnant and leaving an abusive relationship with a "druggie". He shared this early on in our relationship, but I brushed it off as a respectful full-disclosure from him and something inconsequential in his past.

When he announced I was moving in, the ex-wife/BM was upset and cried. I chalked it up to remorse, which some of it probably was. (They divorced because she had an affair.) Still, the BM and I started off respectfully – even having coffee together a few times.

Fast forward a few months to mid-2016. We get engaged and he announces it. BM calls him, very upset, and demands to know why he didn't talk to her about it first. He flatly says he didn't need to. Magically, a few weeks later, I learn she's demanding he take a paternity test for the baby she had in January 2016 – the one she was pregnant with when she moved in with him in mid-2015. Turns out they slept together during the time she lived there, but that part has nothing to do with me, because I wasn't in the picture yet. However, months earlier, she assured me voluntarily that the new baby wasn't his. (I never suspected it or even asked; she brought it up.) To make matters worse – and this is my fiancé's screw up – he waited to tell me about the paternity test demands. He simply came home one day and said he was driving to his ex-wife's house to take one, all while insisting to me it wasn't his. I was livid. I asked why she couldn't come over and have him do it here. After all, she was the one making accusations and he supposedly had nothing to prove. He said he simply wanted to do this to shut her up. I told him he was capitulating and that I felt betrayed. He went to her house to take the test anyway.

The test came back that the baby wasn't his, but I was still angry about the situation. Apparently, she was too. From then on, she wasn't cordial anymore. Instead, she would find stupid reasons to fight... even leaving me messages, calling me names and threatening me.

Example 1: SD's cat injured her tail. SD lied to BM about it, saying I told SD it was all her fault because she didn't take care of her cat. I never said that, but BM took her at her word and laid into my fiancé about it. He asked her if that sounded like something I would say and told her what went on here was none of her business. A little while later, she made SD call and apologize to me. (I was surprised about that one.)

Example 2: SD's friend wanted her to stay the night. The friend's mother wanted to talk to me. SD gave her BM's phone number by mistake. Friend's mother innocently called the BM asking for me by name and referring to me as SD's mother. All heck broke loose. She accused me of forcing SD call me mom, which has never been the case. (Prior to this incident, I flat-out told SD I'm comfortable with whatever name she's comfortable with.) She also chewed SD out, making her cry. Now, she tells SD she's not allowed to call me stepmom either – or at least that's what SD told me.

Example 3: My fiancé's ex-mother-in-law was supposed to pick up SD one day. Plans changed and I went to pick her up from school instead, texting ex-MIL to give her a heads up. The text message: "Hey. I'm picking up SD this afternoon. Just giving you a heads up." BM got wind of this and accused me of being rude, calling me and cursing me out. She also told fiancé and I that I was no longer to be in contact with her or ex-MIL about SD's activities/schedule.

Before this happened, my fiancé allowed BM to have SD every other week, even though the order says he has full custody and she only gets every other weekend. Once this unfolded, he told her they were sticking to the order going forward. He explained that BM's drama and the fact that she neglected to help SD with her school work were the reasons for this. BM came unglued.

Here's the kicker. The next day, everyone was away and I was working from home. BM came over and let herself in my house. She laid into me, saying it was all my fault things were going this way. According to her, they got along just fine before I came along and I was pressuring him to take away her extra time with SD. All stories in her head. She started crying and asked me if I thought she would do anything to hurt SD. Point blank, I mentioned the time she made her feel like crap when her friend's mother called me "mom." I told her that was screwed up and not SD's fault. I also told her I had nothing to do with fiancé's decision and that my intentions are not to replace her. BUT if I was to be doing all these things for SD – helping her with homework, taking her to softball, taking her to dance, etc. – I needed to be kept in the loop. Otherwise, I simply won't do any of it at all. She left and picked up SD from school without clearance from my fiancé. After I told him about it, he told her if she just barged into our house again, he would press charges.

Things are relatively quiet lately. BM still whines to my fiancé about how she feels like an outcast or a piece of trash thrown out to the curb. I don't talk to her at all, letting him coordinate everything. SD had a dance recital over the weekend – and of course BM was there. We exchanged no words, but there's definitely tension and ugly looks from her side. I guess I can deal with that.

Thanks for letting me get it all out and in black and white. If anyone has any thoughts, I'm all ears.