Keep in mind that real Christian unity can only take place in the Catholic Church, i.e., with other non-Catholics uniting with the Catholic Church. Anything else falls short of the mark.
That being said, I have seen a lot of false ecumenism, especially in this country, where Catholics are willing to compromise their beliefs, in order to “not offend” a non-Catholic. Pope John Paul II said that we should always speak Christ’s truths (i.e., the Church’s teachings) with charity, but without compromise. Because, when we do, grace accompanies the telling, and when that person is going to need that grace, it’ll be there.
In my opinion, sitting around the proverbial campfire, singing Kumbaya with non-Catholics is all find and gives us a warm-fuzzy, but until the differences get really ironed out (i.e., the heresies they have in their beliefs get overcome), there will never be Christian unity, because unity can never, ever happen apart from Christ’s truth. There can never be unity through compromise of the deposit of faith handed to the Church by Christ. We aren’t called to be weak-kneed, glassy-eyed, back-slapping buddies of our fellow man. We’re called to love them, even if it hurts. And that often means telling them something that may disturb them and cause them not to “be our friend.” Eventually, it’ll sink in, probably when they’re not in your presence. But not if you never tell them! :o
Just something to think about…