She didn’t ask you? Hmm. Generally speaking, couples review who they want to invite to their wedding together and come up with a list they both agree on. Regardless, it is a very good idea to talk to your bride about this, as it could simply be an oversight. If this is the case and you know the ex and like him as a person, move on from the situation. If the issue was not a mere oversight, you have a communication problem to discuss. Ask her how she would like it if you invited your ex-girlfriend to your wedding without her consent, even if she liked the person. This should help clear up the situation. Should she still protest and fail to see the error of her ways, you might want to reconsider your relationship before saying “I do.”
Again, this may not be the big deal you think it is, especially if you have stayed out of the wedding planning process. You might want to be more involved so you do not get surprised again, such as finding out doves will be released on your wedding day or that the cousin you abhore is coming to see you get hitched.