I'm not keen on the combination with the white jacket. I think this would be best paired with a shawl (purple/blue), a clutch & maybe a pair of stilettos or pointed pumps instead of round toed pumps.
Black is increasingly being seen worn at weddings so I wouldn't be too worried about not being able to wear this dress since it's not overly revealing. The best thing to do would be to check with the couple though, because some races may look at black as being taboo at weddings.