Get your enthusiasm away from me...

I am really sick of sitting in church services and feeling a huge amount of pressure to look enthusiastic! Christians seem to have this perception that, unless I'm extremely happy, I'm somehow letting God down. I hate that! The fact is, most of the time I DON'T feel very excited at the idea of being in church, and I shouldn't have to pretend that I do.
I want to be a Christian, but I want to be an honest one - not part of a mass-self-deception philosophy.