The Bible shows us two things about sin
a) Jesus dealt with it once and for all
b) You still need help from humans to kick its butt
It's weird, I know. We go on harping about how Jesus handled everything, but we're still at the mercy of community. But these two ideas are not opposed.
Community is a vehicle through which we experience Christ.
So if you're caught in sin, remind yourself that you're not going to get kicked out of Heaven because of it. You can still connect with the Father, because Jesus has made it possible. But also tell somebody. Someone needs to know where you are; someone needs to hear your story. Sin brought to light loses power, while sin left in darkness festers and grows. Thus, I say again: experience Christ through the people around you. Tell them what's going on.