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You're not the only girl he's dating.1
You're not the only girl he's dating.
He may not want his other girlfriend to find out.. and if you found out he had another one.. then he is not the right guy for you
It depends on what kind of guy he is. For me it'd be because of privacy reasons. There are cultural and background differences as well. Like the Japanese don't normally even hold hands in public. Perhaps he just doesn't want to take any crap from people, like those pain in the ass questions and whatnot. There are thousands of reasons, not all are reasonable or good.
he's embarrassed by you or just not ready to let everyone know he's dating you...