Quick etiquette question with a short back story:
I was in a wedding this year for a friend who turned into a terrible bridezilla and never came out of that transformation. Since the wedding, we really haven't communicated very much and that's been mostly on my part given how she treated me and others during her wedding planning. After the wedding, she told me how much she regretted her friends as bridesmaids so I took that as my cue to not have much to do with her anymore.
I just got an invitation in the mail to her housewarming party. FI and I are not going to the party. There was no RSVP information on the invitation. I'm torn between sending her a message to say we won't be able to attend the party just for the sake of politeness but FI thinks I could send a stronger message by not sending my regrets and not showing up to the party at all. I can also hear bridezilla's voice in my head telling people at the party, "I just can't believe crabbylucy isn't here! She didn't tell me she wasn't coming! That bitch!" which is why I'm leaning to at least send my regrets and move on.
Do I sent my regrets or just leave it alone?
Thanks!