Usually, when I first join an RP, I find myself somewhere off from the others.
Especially if the RP has a site, after a few weeks/days, I've warmed up, become well-known in the group (Because I'm active), and we're all buddies.
So anyone who's super-shy, I encourage you to push out of your comfort zone at a steady pace, and before you know it, you're besties! xD