Nooooooo That's bad advice. Never start with a negative, as it could turn out there was nothing wrong, but since you ask... blah blah blah and it's amazing what you can find when you are asked.
It's better to say... 'I miss spending time with you, as I really enjoyed our time together and I'd like to see more of you if you would like that too?'
That way you are not making any huge declarations, but simply saying that you have missed not spending so much time together and would like to go back to how it was when you where having fun together and the rest can be said when you are together having fun again.
Go take her to see the new Hunger games film. It's out tomorrow