Goq, first, invites DO get lost in the mail. It happened to me when an entire box of Bar-Mitzvah invitations that I sent to Brooklyn were ALL not received. That was an awkward thing. And even if you are HIGHLY thought of at work, and I am sure you must be, sometimes people have it in mind they did invite someone, when they simply forgot. That happened to me, too. We are all human, and we err. And sometimes little kids help to fill the envelopes and put the addresses on, and they mess up.
And yes, sometimes people just do thoughtless things and invite everyone BUT someone in a specific group.It’s wrong, but it is a part of life. Wish them mazel tov, and be the bigger person for it. You may discover that you WERE meant to be invited. And if not, so be it.
Yaffa80 – You could have easily and believably said, “Oh, I wish I known sooner. Being that I thought I was not invited, I accepted another invitation for that night. But I wish you much mazel tov.” I personally do not hold from that, and just accepted an invite to my son’s friend’s wedding which I received two weeks before the wedding. They said it was an oversight. I take them at tjheir word, but even if not, I believe it is a big zechus to not be broigez, and to be mesameach with someone, even at the last minute.