My sister (36) didn’t attend my (27) former fiancé’s funeral. Do I have a right not want to talk to her anymore?

(I apologize in advance for formatting, I’m on mobile)
I was with my partner for 5 going on 6 years. We were engaged towards the end and I did end things. About 5 months later, he passed away in an accident, it was very sudden and unexpected.
We did remain in communication beforehand and even the day of.
Fast forward to his funeral, my sister did not show up. His family continuously asked me throughout the day where my sister was and I couldn’t come up with an answer because I wasn’t sure, considering we had a conversation in person 2 days prior discussing the obituary.
I asked my sister why she didn’t come and her reasoning was I don’t like funerals and Sundays are the day to herself, I didn’t respond.
Since it was still weighing on my mind a couple weeks later, I sent a long text, what followed was deflection, saying that I should be upset with myself since I didn’t invite her (it’s a funeral?)
Then her husband stepped in and made a group text explaining his side, I responded with a long text explaining how I feel and my sister still refused to see the issue.
Most people agree with me and understand my choice to go no contact, but family members have been begging me to “move on” and “get over it”.
I want to add I understand that grief is an overwhelming feeling, and sometimes anger tends to be mismatched, however, I am upset with a lot of people, not just my sister.
He passed away over 6 months ago.