Would a guy introduce you to his family if you are just 'friends'? By this I mean taking me to meet his parents (he has his own place) introducing me to his son (who lives with the mum) and inviting me to family BBQ.

No! (Not to me at least.) No guy or girl even, is just going to introduce you to their family and most important, their children. If he says you're just friends, I'm guessing he is feeling more than that, but is still trying to sort his emotions. I wouldn't just come out and ask him about it, but maybe bring it up, casually, and see what he says then.