Obligated to say goodbye to untrustworthy person?

Hi everyone. Someone in my community is moving away after almost 20 years of living here. This woman shares some of the same friends as me. One of these friends wants to hold a "goodbye party" for this woman who is moving away. My issue is that I have had many many differences over the years with this woman who is moving. I have endured nasty insults from this woman because of these differences and she has said unkind things to others about me behind my back. I have had some good interactions with this woman, but because of her gossiping and back stabbing behavior I've never been able to trust her. The friend who wants to hold the party knows about my differences with this woman, but just doesn't get involved. My questions is, am I obligated to attend this "goodbye party" for this woman simply because she's lived near me all these years? I feel her behavior matters more and I don't think I should have to attend and say goodbye. Thank you all for any insight you can share with me.

Just say you have something else planned for that time.

Don't go. I just recently declined a social event for similar reasons. I have absolutely no qualms about spending a nice evening by myself than with people who don't value me. You don't even need to explain.

Do not go. Since she is moving away, there will be no repeat interactions, so you are not invested in any way in a potential relationship with this woman and cannot possibly gain anything from attending. Were she a work colleague relocating to another office within the same company and you were obligated to work with her in the future or else risked losing your job, I can see doing something that is unpleasant to you to maintain the decorum and pretend things were ok when they aren't. But you are not obligated in any way and you do not risk losing important assets in your life via not attending. So it is between going and losing your precious time and feeling hurt and not going and losing nothing and gaining an opportunity to do something pleasant for yourself instead, as mentioned above. The choice is clear. And I also agree with the above: do not say that you are not going to attend because this woman has backstabbed you. Just say you already have committed to another engagement on that date and regret you would not be able to attend. If you want advice on how to word it, I am sure there are plenty of good etiquette resources on the web on how to send your regrets when asked to RSVP.

Your number one obligation is to yourself, meaning staying true to yourself, honoring yourself, and honoring your feelings. I don't see a problem with not going. By not going, you are taking care of your mental health, which is also a number one obligation. Don't worry about it and don't feel guilty for taking care of yourself first. There is no obligation to this woman who has not been a real friend to you.