"Freedom is just another word for nothing left to lose..." - Janis Joplin
What we can take from this is the moment you become emotionally invested in ANY relationship, even if it's only hours old, you give part of yourself, part of your freedom of thought to it. From that moment you can place any number of metrics upon yourself, correct or incorrect, that will in the long run effect who you are. With that investment of emotion the actions of the other person involved will help shape who you are.
What we all strive for as human beings is FREEDOM. Freedom to do as we please, which for many of us is finding a person who is special to us, who completes us, who fills the voids. It is understandable to seek actively to do this, nobody likes being alone. Regardless of the number of friends, fuck buddies, acquaintances or family we surround ourselves with, most of us will continue to feel at least a little alone till we find that person. Where am I going with this? Enjoy your freedom, don't invest in a relationship, even a little bit, until you feel it out and figure out what it is going to mean to you. Each of us looks for something different out of our relationships, you have to figure out what you are looking for in yours. Any relationship that doesn't appear to bring you closer to this goal should be taken as is, accepted as it comes and goes, and plainly communicated to the other person involved exactly what it means to you. These little relationships we have with people will fill that void, make us feel less alone in the short term, what you have to do (in my opinion) is take it from Janis, be free, only put yourself in a position to feel loss when it's worth your freedom to look for what will bring you happiness in life. If you have a quiet night of kisses and cuddles (and I have had my share, who doesn't like kisses and cuddles) then enjoy it in the moment, look back only as the memory of a moment in time where you were content and let nothing take it away from you. If this boy means something to you, CHASE HIM. Most people (men and women both) often need to be chased to some degree or another. If he has discarded what you had, and you believe he might be the one to bring you happiness then give chase, let him know you are interested. Make him tell you he isn't, it might hurt, but there are no regrets without action, and there is no success without failure. If he's not worth chasing, don't let it plague you, just enjoy the memory. Look for the one who is worth the chase, and make him see who you are, there is no doubt in my mind you have much to offer a potential partner, but until you make them look at you, they will never make an informed decision, or give you an informed answer.
Just my opinion.
P.S. This doesn't give anybody permission to stalk anybody, be reasonable people :P