I HATE BEING SINGLE!!!
Well, at least you've recognised your problem.
Now, do something about. Be an asshole. Pretend that you were the one who decided to terminate those relationships and that they meant nothing... and start looking for a new one right away.
Or go the alternate route and attempt to start a new relationship, but take it slow. That way if it fails it would have meant little to you, as it probably wouldn't have been very developed.
This person speaks of the truth.
Generally just try and be outgoing, take care of your appearance, and you'll do just fine. Learn how to speak with women, have some conversation topics ready to go, and anyone should do fine.
Don't expect to take a shower, get dressed, go to a club, and find a long lasting relationship, but hey, itll be a start.