I have a question are you mixed religons? Because I am half sikh and half christian and my parents aren't really that strict about religons. Sure when I was younger like around 12-14 my parents  made me to go to the church really often but now that I'm older they don't force me to do stuff anymore. Well I don't know how old you are but I'm 17 and my parents know that if they try to limit me or make me do stuff that I feel hesitant about doing I'll just drift apart. If I tell my parents I wanted to be an athesit they would argue with me and say that I shouldn't give up my religon or I'm just mad cause of something but after a while if I keep saying I wanted to be atheist and giving them tons of reasons they would let me do what I feel is right. We all know that there is the emotinal blackmail parents give but you should do what you want to do or what you think feels right. You may make your parents happy by praying everyday but does that make you happy. Surely one day your parents might find out that you want to be an atheist what will you do then? What will you do if they ask you why didn't you tell us that you don't believe in any sort of religon? Your parents will always support you the most if not then try tell your teacher or proffeseur maybe even a close friend that  you can trust and you both can go and convince your parents. If your really scared that they will be mad about you telling them that your an atheist think about what happens if you hide it from them. They will fell rejected and vent out more anger on you. So I think it's best for you to tell them now before it's too late.

Copied from a website I found:

First, the Bible teaches that people should not judge. This is often a difficult guideline for people to follow. Judging people is commonplace, and people often forget it is against the teachings in the Bible. Because of that, people judge for a variety of reasons. Most often, they judge people for being different. However, the Bible cautions against this kind of behavior.

The Bible also says to accept everyone. It is not the job of humans to decide who is right and who is wrong. Instead, people are supposed to be accepting. They are supposed to live their own life the way it is supposed to be lived and accept the decisions others make fully and completely.

When people are able to live their lives without judgment and with acceptance, they are then able to love. Love is what the Bible is about, but that sometimes gets lost. When someone truly follows the Bible, they love everyone without stipulations. They do not put conditions on their love. They do not make people share their ideals in order to love them. Instead they love everyone, just as Jesus did in the Bible. They do not try to change them. They simply love them for who they are.

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If they are truly religious people (which with what you have said, they seem to act in a way where they believe they are religious), then while they may get upset at you for a while, they will not let it carry forward and continue to judge you based on this, that would be God's job, not theirs.

I truly do think that you should tell them, because hiding something like this from your parents for your whole life (if you can't tell them now, you will have just as much or more trouble telling them later) just isn't right.

Just stay quiet until you move out, since from your description of them that seems the most sensible decision.

FINAL UPDATE: Couldn't get communion because I eat meat. Also managed to get out of confession. Safe for now. The charade goes on, I guess.

Thanks for all the advice everyone!

Now that's one hell of a solution. Works well and tastes great. Had no idea you couldn't do it if you ate meat.

Anyway, good luck.