You just need to relax. You are over thinking this way too much. First of all there is no such thing as "not enough clingy". You should never be attempting to act clingy, overbearing, or the like. Being patient is the best solution here. Odds are there is something else going on behind the scenes here. I don't know how much you know about this guy's life, but maybe he has other issues that you don't see. First try to find out if there is something going on in the other parts of his life that are affecting him this way. If he doesn't open up to you, well that really sucks. All I know is that being the girlfriend who constantly worries about a guy and is always checking to see if everything is okay (works the same the other way around too) is very unattractive and is not how you are going to break through to him. My honest no BS solution if he is suggesting the problem is you is to stop paying so much attention to him, and if he really likes you he'll come around.
Cheers and good luck
