White to Wedding?

How mad would you be if a guest wore a white blazer to your wedding? Something like this. (Pic below). The bride will be wearing a white dress. I was told it's rude to wear white. I totally forgot I had a wedding to attend. Preggo brain. It's the only thing decent I have. 
**Update**
Checked with the bride. She said, not to wear white! 1) she should be the only one wearing white 2) the family pictures will look better if only she's wearing white.