Guy drama...guys and girls answer seriously help me out?

Ok well i like this guy lets call him craig but i am dating this kid devan due to the fact craig dint want a relationship but were both in love with each other. Do not give me this crap about me not knowing what love is, i am old enough to know what it is thank you very much. I do not DO NOT love devan i love "craig". Anyway devan doesnt want me talking to "craig" so i sent him a text saying that and before that he was acting all happy for me and devan. When i sent that text he texted back "...bye" before that he was asking why devan did not want us talking. Please tell me what Craigs deal is and why he doesnt want a relationship. He also asked me the other day before me and devan started dating if i would be ok sharing him with another girl since we werent dating. I said ok but it was clear i was jealous. He promptly stopped talking to her.