Ordinarily, I’d tell her how hurt I feel.
Dear Worried: It is not rude to go to a wedding ceremony but skip the reception, but you should notify the marrying couple beforehand so they can rearrange their seating.
You could certainly be honest about your reasons for skipping the reception, but this wedding is not about you.
If people don’t wish to respond, that’s their right, but then I have the right to avoid them.