Troubles with bridesmaids

If you like wedding drama buckel in and grab some popcorn. My wedding is in June of next year and wedding planning has been smooth sailing for the most part. My sister is my MOH and my "best friend" a bridesmaid. My sister and I had a misunderstanding and I was talking to my friend about my frustrations with my sister, my first mistake. Talking to my friend apparently emboldened her. I told her I was going to start doing things on my own because my sister showed no real interest in helping and boy oh man did this piss my friend off. She got all in a huff and told me it sucked for me to do things on my own, not that it sucked for me that it sucked of me. I wasn't willing to do things for my wedding without my sister's involvement and she thought that's exactly what I should have done. She got in my face and told me I needed to give my sister an ultimatum, either get interested or get out. I said absolutely not. She also clapped at me about how good of a friend she is to me. Before this exchange she asked me to invite some of her friends seeing how I chose her 23 y/o boyfriends birthday as my wedding day and he would be alone because she's in the wedding party. She said and I quote "you have to consider other people too". I am by no means a confrontational person in fact I will do almost anything to avoid it. I am also not a inconsiderate person but I feel like that was pretty rude. The friend of hers she wanted me to invite I've hung out with on three occasions and after the second I really didn't want to hangout with her again but we had all bought tickets to the same show so it made sense for us all to go together. My 2nd mistake. After getting in my face I needed to take a step back and get my thoughts in order before I said anything before I got my head straight we went to this show. They wanted to make a day of it so we did from the time I got in the car and all the rest of the day I was ignored and VERY excluded. It was obvious to me she had said somethings to her friend and neither of them wanted me there. The next day at work I was pretty beaten down, I think anyone would be after a whole day of that, she seemed to get a kick out of it. Now I want to say that during all of this I was not rude to her I was distant and not as chatty as I normally would be but I made it a point to not be mean or rude. She knew something was up but never asked what. I am going to have a conversation with her but at this point I don't know if I want someone like this in my wedding, let alone my life. I'm not making this post to bash but to ask for words of wisdom in dealing with this issue. Honestly any advise would be appreciated.