If you really want this relationship to work, you probably gotta find a way for you to both receive what you crave, if you already have had the urge to cheat a second time, then you have to act quickly. Cheating is an active choice, and if you feel like you have to because he doesn't give you the love you need, maybe this relationship isn't for you. Communication is key, and without it you'll be lost, if its hard to actively communicate with him, then seek some help from others. Also if you aren't already taking any, consider medication, its not for everyone, and sometimes makes things worse, but give it some thought.
While this isn't my strong suit, I think that the most important thing is to just do something, figure out the core problems and fix them.