WIBTAH for not wanting to go to my aunt’s 60th because of her partner?

I posted here about a year ago after my aunt’s boyfriend (who I’ve always considered basically an uncle) made me extremely uncomfortable. He had touched my bum when I was younger, and years later did it again at a family party while also openly flirting with me and commenting on my appearance. I ended up having a panic attack at the next family gathering and haven’t felt comfortable around him since.

My aunt eventually found out. He denied doing anything and said I must have misunderstood, although apparently there had been other issues with him being inappropriate in the past. My aunt initially confronted him but ultimately stayed with him.

There was also a family discussion where he was meant to apologise to me. I refused because I didn’t want an apology that involved him telling me I misunderstood or blaming alcohol. Since then, I’ve mostly avoided family events if I know he’ll be there.
A few weeks ago was my cousin’s confirmation, and unfortunately he was there. I went because it was important to me, and he basically completely ignored me the entire time. He wouldn’t make eye contact with me or speak to me, which honestly made things easier for me, so I just kept my distance too.

Now for the actual update: my aunt has invited me to her 60th birthday party. Obviously, he’ll be there, and honestly I really don’t want to go. I feel guilty because it’s a big birthday and she’s my aunt, but I also don’t see why I should put myself in a situation where I’m going to be anxious and uncomfortable around someone who has behaved like this towards me.

So AITA for not wanting to go / potentially deciding not to attend her 60th?