You can still stay in touch with that persons via facebook, skype and other social websites. But be realistic. Don't build up expectations. As a single girl, you have more time and more freedom to do all the exciting things- travel, learn new languages, develop yourself as a career woman, get new friends, make some cool purchases..
I have also been let down by my previous relationships but they have taught me some valuable lessons. Don't dwell on that break up. Meeting friends and family members can help you get your mind off the break up. There are millions and billions of guys out there..You will definitely meet someone who suits you even better than the guy you broke up with.
I truly believe everyone does come into your life for a reason. The good, the bad all add up to make you the person you are.
You knew it wasn't gonna be long term, he made you feel good about yourself. Go be that confident, happy vibrant woman he saw and someone will see all that goodness too.
I understand. The hard part I guess is that you both knew that going into the relationship. Can you still be friends?
Get used to it. The longer you live, the more you realize that you are totally alone, except for fleeting moments of others who pass through your life. No acqaintance is permanent.