Is this dress too short for a wedding?

Is this dress too short for a wedding?

The friend of a wedding guest took to Facebook to detail her pal's agony at a wedding and all over a dress.. (the one pictured above) She wrote:

"She says she got treated rudely by other women at the wedding who saw her as a target for wearing this dress. A woman came up behind her and slapped her on the bum and said it was on a dare from a group of other women who were watching and snickering. 
"Someone else seemingly purposely spilt a beer on her.  "She's amazed that grown women could be so immature and such bullies.  "But wait. She wants to know - did she bring ANY of this on herself by wearing this dress to a wedding?" 

Some commenters think she stole the couple's shine while others think the dress would have been appropriate anywhere else but not a wedding. Thoughts?

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