For me, it's also the same. I feel that I have become distant and somehow, like you said, 'close'. You're not the only one. I think it's due to growing up: as we grow up we have learnt to become more independent and we do not need their guidance as much as anymore.
Of course, many things could have happened as to why you feel this way. Perhaps, there may have been some argument or comments that have hurt you, which inevitably caused you to feel somewhat awkward.
There's nothing you could really do but communicate with them. Although you said communication will probably render useless, expressing how you feel to another person will give you that understanding. I'm sure that there's a reason behind this. I wish you all the best.