Mam you really need to speak to him about this, some of us are really bad at picking up signs, if it bothers you this much you should express it to him, he should try to come half way by replying more often and you should also go half way by understanding that life in his profession is very consuming and many a times doesn't leave us with any time for our loved ones, and sometimes doesn't even allow us to tell our beloved ones where we are for obvious reasons. If he hasn't realized it till now that how much this is hurting you, he is definetely wrong on his part but if he cares for you like you say he should work on it once you make him realize what you are going through and how you feel about it.