Odd Behavior? Odd Patterns? Thoughts wanted

35m family scapegoat that went no-contact 2-years ago mainly due to the contrast between how I was treated versus my Golden Child 37F older sister who continuously demonstrated objectively selfish & bad behavior but got a pass every time by my covert n dad.. meanwhile I was vilified and demeaned for calling it out.

Short backstory: Its been two years of no contact with my family and since going NC I've been able to take a step back and observe her behavior and it genuinely baffles me:

• she has left me 3 voicemails
  • one on NYE where she just says happy new year
  • another 1-week before my wedding anniversary in June where she says "i'm so loved and valued and the door is always open..."
  • Another on my birthday where her tone is so casual its like we talked last week.. when its been 2-years
• She has sent 4 cards throughout the two years
  • each card is eerily the same message give or take a sentence: "you are loved and valued and your family is always here for you..door is always open etc."

Here is where I need your help:

In all of her outreach (VMs/cards) she has never asked a single question... she has never directly asked why have you stopped talking to me. She just writes/leaves VMs like everything is normal when we haven't spoken or communicated in over 2-years..

In all of he outreach she frames it like the door to the family is always open ... but she never considers that I'm the one who closed it purposefully and she may not be welcomed in my world anymore from my POV..

Her outreach always seems to come on special occasions [NYE, Birthday, Wedding anniversary] like 'oh I need to check the box to be perceived as a 'good sister who tried' ... but realistically if I were to actually answer the phone are really going to have a deep discussion, heal and get through all the pain on my birthday, new years or my wedding anniversary? These gestures come across as hollow checkpoints to me.

Questions I Have:

• Am I being overly critical?
  • She could always text or call my wife if she actually cared and wanted to understand why I stoped talking to her and blocked her from everything..but imo she doesn't actually care this is all performance
• Is her behavior super odd?
  • Her most recent voicemail was so casual and the tone was like we spoke just last week..but the reality is when haven't talked in over 2-years. No mention of our estrangement or anything.. it was super eerie
• Does she really think any healing will occur on these milestone dates?
  • or is she doing this deliberately reaching out on those special occasions to mess with me or something?
• How has she not asked a single question in over 2 years?
  • If she really wanted to repair our relationship & the damage done wouldn't a sane person ask: "Why are you mad? What can I do to repair our relationship? What did I do to make you so angry with me?" .... all she does is just state useless platitudes over VM or a card like 'you are loved and valued, and the family door is always open to you.' like wtf is that?

If I sound a bit harsh its because admittedly I do have a lot of anger and resentment towards her, and her behavior since going no contact just confirms what I already knew.. she only cares about herself and doesn't make any real effort only hollow gestures.

Would welcome any thoughts, observations, blindspots, advice and brutal honesty as outside of my wife and therapist I don't really have anyone to talk to about this. Thank yoU!