
I used to feel awkward if I didn't get a reply, but not anymore. I got in the habit, when I was bored, of sending /tells to anyone who looked like a RPer asking if they were, what sort of RP they liked, and if they'd like to RP with me. I'd say easily 50% of them wouldn't reply for various reasons (afk, shy, thought I was a crazy stalker, etc), so I got used to that pretty quick.
As an aside, I heartily recommend doing this, especially if you're the sort of RPer who normally stays quiet and wishes they had more RP going on. It gets you in the habit of talking to people you don't know, it gets you in the habit of asking people about the RP they want (and honestly, you're far more likely to get interest from someone if they think you're interested in what they want), and it gets you a big-ass friends list full of people to RP with.
As an aside, I heartily recommend doing this, especially if you're the sort of RPer who normally stays quiet and wishes they had more RP going on. It gets you in the habit of talking to people you don't know, it gets you in the habit of asking people about the RP they want (and honestly, you're far more likely to get interest from someone if they think you're interested in what they want), and it gets you a big-ass friends list full of people to RP with.