I think if you go depends on how crappy you'll feel. If only awkward or weird go. If you'll be devastated to see them don't.

That being said I think the ideal is if you can go and show that you're OK without her. Not because you're with someone else who's cuter, but because you don't need her

Me-38 W-38; T-15 M-12;
S10 and S6
BD - July 2016; EA confirmed; confronted Aug 2015
EA dissolved 12/2016

Never make someone a priority when all you are to them is an option - Maya Angelou