Should i hang around or call it a day?

Met a guy through a friend, at first he would just visit, kind of daily actually. He never showed any interest romantically for a while and i wondered what his deal was so i asked a friend to casually ask him what was happening between us, his response was that he was getting to know me, checking me out. My friend and i were puzzled by this response, and she didn't get the opportunity to further this conversation with him as someone interrupted their conversation so i then decided to start flirting with him. About two months later our relationship started and i was being introduced as his girlfriend. Now, about three months into the relationship, i feel like he's not totally into me. He has a business that consumes him, mentally, entirely and pays attention to me when he has no other commitments. Its confusing cause he does nothing wrong, but his communication and the way he treats me is seeming quite casual, he does the routine stuff but hardly goes out of his way to make an effort. I've been disturbed by this so much that i swallowed my pride and spoke to him about it and I'm noticing that he's not quite getting it from my point of view. In trying to be fair and mature about this i've tried to decrease the pressure on him and kind of live my own life in case he's not sure how to tell me he doesn't really want this, but then he responds by calling and texting, appearing to be confused by my disappearance. What i think is, two possibilities, that a relationship is not on his cards at the moment because he's got so much going for him, the other is that i'm not what he really wanted but he's in it and busy so he couldn't care less to think about it (i'm available and just an accessory) but I know i might be wrong so i need a little help because I'm starting to get frustrated with him when he doesn't respond in a desired way, and i'm trying to be as fair as possible but its not looking good. i also don't want to loose out on a good guy for a silly reason when there might be an explanation or solution to the problem. I'm also a realist so i don't want to hang around till he finds what it is he's looking for, neither do i want to talk to him about it again cause now i'll just loose more of my sanity and dignity as he doesn't really change either way, he just kind of tries to make up for it by calling more or trying to say things he thinks i want to hear, nothing sincere in my books. Should i stick around or call it a day?