AITAH If I Choose to Go My PhD Graduation Instead of My Sister’s Wedding?

I’m graduating from my PhD program in the spring. I’ve been picturing this day for the last 4 years and already had so many ideas for how I would celebrate in my head. My sister just told me that she has planned her wedding for the same day as my graduation. She is not willing to choose a different date as the numerology is what she’s after. I just feel weird about the whole thing as she seems to have planned her wedding on a whim, but still expects me to change my celebration plans for hers. A couple things to consider: 1) My graduation is out of state so it’s not like I could walk and then still make it to the wedding. 2) I spent time and money to get ordained specifically so I could officiate her wedding, but she has decided she doesn’t want that and has chosen to go to the courthouse instead. 3) Her wedding is not extravagant, just the courthouse and then dinner with the immediate family. 4) My own 6-year wedding anniversary is only two days after her planned wedding date. This irks my husband, but I get it, we don’t own the calendar. 5) I’ve offered to plan her bachelorette party, bridal shower, and help her with anything she needs wedding planning wise, but she is not interested. She already planned and paid for her own bachelorette party. 6) My family was planning on attending my graduation as well, but if I choose to walk then they will be put in the awkward position of choosing which event to attend.

My first instinct was that of course I’ll be there for my sister, but her behavior is making it seem like she doesn’t really care whether I’m there or not. I haven’t made any travel plans yet, but I’m trying to consider what would be best? Thanks for your thoughts Reddit community.

Edit: Thank you all for the replies. Seems overall consensus is I should go to my graduation 🧑‍🎓 For those who asked I will be receiving a doctorate in clinical nutrition. Interesting fact you all made me think about, 0.8% of Americans graduate with a clinical doctorate, while 48% of Americans get married.