I would attend neither. This is like when a certain man in Asia was brought to court for being Catholic and they tried to persuade him to apostatize. When he refused, they said something like "Don't you love your wife and children?" and threatened to kill them if he wouldn't apostatize. The man said, because I love them, I will be a good example for them and not abandon my religion. (This is just a summary of an account that I read -- you can read it in "The New Glories of the Catholic Church") I think that you can apply this example to this situation.

Don't just take my advice though, do what you think is right.

It's a difficult situation, Alex -- and I always hate to give hard answers.

I think the "standard" for what a Catholic should attend is: "Is this marriage even valid?"

I think it's one of those things where you should go out of your way to be charitable to him (and his "wife"), but gracefully not attend the wedding. I think you know what I mean. There need be no fireworks; you can be calm and cheerful the whole time.

If you don't attend the wedding, yet you don't yell, argue, etc. but on the other hand are very charitable to them -- it will be the most you can do to make them stop and think. By acting like a saint in this way, they won't be able to easily pigeonhole you.

My wife and I already agreed that we won't be attending any "second marriages" of any friends or family. That's our cutoff. We've been to several Lutheran weddings (college friends of my wife, and one sibling of hers), but they were a first wedding for the parties involved.

I mean, those people are non-Catholic (or fallen-away Catholic), so they objectively commit a mortal sin every Sunday by not attending Mass -- but do they commit a mortal sin subjectively? Do they realize their obligation before God, and that only the Catholic Church can save them from Hell? Only God knows.

I think a Catholic's goal should be "How can I make the maximum good impression of what Catholicism is all about." and, of course, it goes without saying that EVERYONE should think of Catholicism when they think of you. If they don't, you have a bigger problem.

We have relatives that know instinctively that inviting my family to dinner on Friday means they need to have seafood or vegetarian fare on the menu. And I bet if anyone asked many of our relatives about us and birth control, I'm sure most of them could answer confidently that, "Oh, they're Catholic...I mean really Catholic...they don't touch the stuff."

I think that's a very good thing. It can be uncomfortable to be different, but it's worth it when you know you're doing your job to witness to the truth.

Matthew

Unfortunately, it's most difficult when you're the sole person who objects to the union.

I've seen situations where the family is predominately Catholic, so the person wishing to marry outside the church (or make other similar non-Catholic decisions) pretty much understands that doing so isn't going to meet with family approval. For example, one individual got married out of state so her family wouldn't have to bother telling her they wouldn't be there.

If you don't attend the wedding, I wouldn't attend the reception either. In fact, I think if I were choosing one just to maintain peace within the family, I would attend the ceremony and skip the reception because it is a celebration of the "wedding".

Vlad....attend your brother's wedding!!! Sure it might not a trad Catholic wedding but it is your brother of God's sake. Don't make enemies with him and his new wife? Help them celebrate their new life together. Let then see that you care...

I say go to the wedding and give both a big hug. Later on, if you so desire, you can try to convert them.  

"Help them celebrate their new life together" ? You mean their new life of concubinage? Are you even Catholic?