Confused and need advice.

So my husband and his friend have been friend for awhile now for the longest time I had never met his friends girlfriend. When I finally did met her she came off as a decent human being, love bombed me and kept telling me how much she really liked me. I Suspected something was a little off with her but I always give people chances and like to see the good in people. I must admit 2 people had came forward and told me to stay away from her because she is not a good person and a narcissist but I didn't listen. After while I started to see signs that something just was not right with her. She would cut me off and over talk me while I was talking and switch the topic back to herself, When we would be out walking for exercise she would walk in front of me leaving me behind so she could be in the lead, Give me back handed compliments the list goes on. When I became in engaged she laughed instead of congratulating me and said I over her my boyfriend talking to your fiancé and said I figured it was coming but didn't know when. She would get angry and upset with me when people would tell me my engagement ring was beautiful so she started out of nowhere wearing random rings on her ring finger even though she is not engaged (I honestly think she did this because she is jealous and wanted the attention that I was getting). I had a private shopping party for my bachelorette at a local boutique where I know the owner we were all having a good time but all my friends noticed that she was not treating me nicely and rolling her eyes at me and making snide comments but I didn't let it ruin my day. At my bridal shower she was going around making comments to my friends that I knew my bridal shower was today because I had a new dress on. ( I had no clue my bridal shower was happening I was told we were going to brunch with my best friend and her husband. Prior to this I wasn't hanging out with her as much because I always felt drained after being around her and just didn't feel myself. I honestly didn't even want her at my wedding but I had to suck it up because my Husband is good friends with her boyfriend. At my wedding she for the most part acted decent but she complained about a small handful of kids being at my wedding and she also went up to my friend whom she had only met once and made her feel uncomfortable and called her at saying I facebook messaged you inviting me out for drinks and you never responded. I suspected something was going on so I walked over and my friend thank you so much for saving me she is crazy. ( She had to block her) She was also standing very closely next to my pregnant sister in law and made her feel uncomfortable. She always was talking to my other friend who she only met once at my bridal shower and made her feel uncomfortable as well. Non of my friends like her so it's a huge sign. Now that my husband and I are married I no longer have contact with her, she continues to blow up my phone begging to hang out and I just blow her off and tell her I'm busy because I no longer want to be around her. I have spoke to my husband about this and I have tried to be cordial with this women because he is really good friends with her boyfriend but I just cannot do it anymore. And Ms Nutcase has already started putting a bug in her boyfriends ear saying now that we are married we are to good to hang out with them which is not the case. It's her she's the problem. I am honestly at my wits end and do not know what to do. I want my husband to still hang out with his friend but its putting me in an a stressful situations because they want to do things as couple but I cannot be around someone who is so toxic. Please Help! Thanks in advance.