Geez Alice, seriously, chill. You can have a reasonable discussion about Catholicism/religion and atheism without being so condescending. I've had them myself with Andy, where he wasn't aware of some aspect of the Church, and instead of lacing every sentence I wrote with the implied "I'm smarter than you" that you are, I explained it and he understood and there was no conflict at all. I know you're a devout Catholic, but you shouldn't let Andy's opinions sway you to the point that you're rude to him because of what he feels.
My question to you is, how is Confirmation something necessary to your faith? Why do you need to go through a ceremony and say in front of everyone in the Church how you feel? And if you feel the need to, why do you need a ceremony to do it? The only point of a ceremony like that isn't to "confirm your beliefs", you can do that any day you want. I'm sure if you asked your priest if during parish announcements you could announce to the entire Church that you still believe, he would be more than happy. My old priest would have been fine with it at least.
The problem is the requirement of it for Catholicism. It goes hand-in-hand with evangelizing people. It just is not something everyone should feel forced to do. You can believe in everything in the Nicene Creed without feeling the need to go tell everyone you know how much you believe in God.
It's easy for you to say "you should just believe it 100% completely or not be a Catholic!", but you're in the uncommon position of having been raised in a highly Catholic-friendly household where you were given "God exists and is all-powerful etc etc" from a very young age. As much as I'm sure you like to think that that doesn't affect you, I'm just as sure that it does. But for others, who actually struggle with faith and want to believe but can't accept a certain part or something similar, Confirmation to them is a one-way gate, where if they say it and they're still struggling, they're now trapped. But you can't be a full Catholic without Confirmation. So they're barred from the full experience of Catholicism because they're not 100% sure on their beliefs. Which means they can't make a full decision with knowledge of what being a Catholic entails, because how can you do that without the Holy Spirit?
In addition, you can't just dismiss the way Confirmation is done nowadays by saying "well that's invalid so let's not talk about it". Andy is right in that it's often shoved upon people at a young age as 'the thing to do', so these kids are now Confirmed in something that they don't even truly believe in. It happens to adults too, because not all adults are as stubborn and argumentative with everyone around them as you seem to be. I was Confirmed at 16, fully old enough to understand the words I was saying. That doesn't mean I made a free choice, because I became Catholic due to my mom's wishes. But regardless of whether that Confirmation is "valid", it still acts as a gate that locks you in whether or not you want to be.
It's unrealistic to expect everyone in their lives, once they decide they're one religion, never have doubts or change their minds. In the perfect world of Catholicism once someone sees the light they'll never turn back to the darkness of hot, hot pre-marital sex, but in reality peoples' minds change and the act of Confirmation makes them feel as if they aren't allowed to leave the Church. Once again I ask, why is this necessary for Catholic faith?