Christianity is about the relationship, not the actions. The actions are the result of the relationship, and just like my marriage doesn't look like everyone else's, neither does my relationship with God. Instead of focusing on "How are they doing it?" and "If it's ok for them it's ok for me" or "They can't be right if they're not doing it the same way as me", we have got to come back to our own personal relationship with the Father. And a personal relationship with the Father is all about the asking, the rapport, the we-want-to-follow-YOU-not-some-idea-we-swallowed.
I've heard it put this way: We fellowship around the Life that we have, not the Light that we have. The Life is our Lord Jesus. The Light is what He is showing us in our own lives. He is not showing us all the same things at the same time. If we try to fellowship around the Light, we will all quickly become frustrated with one another and go our separate ways. If we fellowship around the Life that we share, we can rejoice and encourage each other.