What can i do to change his mind?

recently i finally got the guts up to tell my friend/crush how i felt and now weve been together for 3 months which have been great...but when we first started dating he laid down some..conditions? 1 that he doesnt believe in love, so he didnt want me to get that attatched 2 no , becuase he felt it would lead to 1...he had just learned that his long time love cheated on him with a ton of guys, including their drummer, so i get that he has trust issues with that kinda stuff...but i REALLY cared for him before he asked me out, and 3 mnths later, i think ive broken rule number one...and then he let me break rule number two, reluctently as it was my first time and he thought that would do it, but he didnt realize i was already in too deep...i want him to trust me enough that i can tell him 'i love you' when we fall asleep or when he leaves my house, but i dont know what to do. there is also the small problem that theres a good chance that he could leave with his band in november, its only an hour away from here, but its vegas...aand he'll just be turning 21, and i rarely get to spend time wiht him when band things are going on anywya...but yeah, i have some problems lol...i need help....