Excellent! One suggestion, though: wouldn't "space" work better than "millimeters"? Millimeters is such a harsh scientific term (I mean yeah we all use it, but it has that harsh exact sound, cold and to the point. Just the facts, ma'am). Also "space" would keep the mystery going longer - are we talking about a relationship or something else? using millimeters kind of gives it away.
That is a really great suggestion. I wish I would have thought of it. I don't usually incorporate suggestions into my finished poetry as I want it to be 100% me. However, in this case, I feel I have no choice. I will give you credit if it ever gets published (which is highly unlikely).