My sister and I haven't spoken in nearly two years, except for a couple apologetic emails that I sent her right after our falling out. We were best friends but also kind of toxic, grew up in a very dysfunctional, enmeshed family. I'm convinced my sis has NPD and my mom has HPD or BPD with narcissistic features. I've posted about my awful relationship with my mom before. Anyway, my sister and I had a very bad routine at the holidays of getting extremely drunk, often times crying and bonding, staying up all night talking about what a messed up family we had. 2 years ago, we got black-out drunk (she drank almost an entire fifth of tequilla herself, I was drinking vodka) and had an altercation. I don't remember a lot of what happened, as we were both in black-outs when it happened. The next morning, I woke up with a sense that I needed to apologize to her. I told her I owed her an apology and she didn't even know what I was talking about.

As the day went on she said it started coming back to her. I apologized profusely but she did not want to interact with me anymore - at all. As best I recall I told her my unfiltered thoughts about her emotionally abusing her long term boyfriend and how she was the problem not him. (Like I said, I think she has NPD, she was extremely verbally abusive and emotionally abusive to him.) Obviously this was not a nice or smart subject to bring up, I have always taken full responsibility for what happened. Since that Christmas two years ago, she has not seen or talked to me. She asked me not to email her, she blocked me on all social media. She told my mother I "assaulted" her and no one is sure what she means by that. I have always been up front with all of our family and friends that I was in the wrong, and I have been apologetic the whole time. Even though I know that our relationship was very toxic, and that I am better off not being close to her like we were and likely she is better off as well, I am sad that my sister is not in my life. I wish we could have some sort of relationship, even if it is just to send Christmas and birthday cards. Not act like the other person doesn't exist.

The other day, I woke up in the morning with a strong feeling that I should send her a Christmas card. I talked to my boyfriend about it and he said that as long as I am doing it for me, and not expecting some reaction or response from her that I will be upset by not getting, that he thinks it is ok to do. I think it will probably be ignored and at worst get an angry email. I can't imagine her reacting positively to it, yet I cant shake the feeling that I want to do it. Is this a bad idea, given that I know she won't be receptive to it?