How does one become okay with being single?

[mr.moons]

Hi.
As you can see, I am new here.
Umm I guess I'll introduce myself a bit. I'm from a pretty northerly city in Ontario, Canada, but now I live in the Greater Toronto Area. I am a male as my username suggests, and I am straight. I'm not gonna tell you my age, because I don't think doing so would do any good, plus you'll probably be able to narrow it down to within a few years without much difficulty.
Anyway.
Here's my problem: I've been completely and hopelessly single for a little over three years I guess, and I don't dig that. Also I've never actually been in anything that could be called a serious relationship. Officially, my longest relationship lasted two months, and my most intense/involved/meaningful ones (or at least they felt that way) were both long-distance, and based off of online communication.
Some people don't seem to care about finding a significant other, but so far I haven't been able to get myself to be like that. I just have this strong desire to experience a loving romantic relationship, but that desire is profiting me nothing.
So how would I go about becoming content with this single life? It seems like I need to change my emotions, but is that even possible?