Do you have to pretend to be religious to fit in?
I've learned to be me....and if they can't handle it fuck em. I live in the Bible belt and you can't throw a stick without hitting some church, synagogue, mosque or house of worship around here, but I push back when they start in with all their mumbo-jumbo crap.
I normally just go with the flow if it is in a private household and this is what they believe or normally do. However my last job was working for a church and although I loved the work I often felt uncomfortable when it was suggested I attend church sessions. I felt that if I respect what they believe they should also respect my beliefs.
I have a direct question policy. I keep my lack of religion quiet unless asked directly. I generally scoot around the most common question "What church do you go to?" with "I don't have a church. I've never found one that works." Then they, of course, plug their own church; I reply "thanks, no thanks." and go about my day.