Why does ending things never feel good?

I ended something with a guy and although I know its for the right reasons I still feel a bit sh*t!

He invited me to a wedding and he still wants me to go with him.

I haven't said I would but this is part of the reason I'm ending things.
I feel like I'm there to make him look good.
His needs seemed to come before mine always and even now.
I get it, who wants to go to these things alone?
But we're no longer together.

Even if he'll keep his hands to himself as he promises...