communication commitment

in my opinion a relationship is a union where both sides should be consistently treated with the same amount of respect by their partner. but what if the guy's communication waivers??? say the guy for a majority of the time is extremely into you, but there are times that you question his fidelity or commitment to the relationship, what do you do? for instance when i call and he tells me he'll call me back in 5 minutes, i expect a call within the next half an hour, but if i have to wait 5 hours to hear back and even then there was another call and a bitter text sent, what is the proper way to handle this situation? get mad and go off on the boy? interrogate him? ignore the indecent completely? give him the silent treatment? what? i hate having someone who has a hold over me like this! the silent treatment would probably be the route to take, but i think for tonight i'll give him one more call and then hit the hay regardless... there's no use going to bed upset...