The queen has no real power in canada and therefore I am fine with her being head of state. As head of state the queen can remind us of out heritage and the history of this nation. As long as our elected representatives continue to make all significant decisions, the queen does the important job of reminding us of where this country began.
Heritage is who you are, and without the Queen, America, Canada and far more civilised places would not exist as we know it.
You'd be forever loving and respectful of your parents, so how is it any different?
I wouldn't disown my family after a while just because I'm no longer dependant on them, the principle is the same.
I already find it silly and disturbing that Americans disregard their British 'Parents', because without us they wouldn't exist as a great country, if at all.
The world owes an awful lot to the British, and in my opinion are nowhere near grateful enough.