A girl (or them) were once holding on to a relationsip, constantly calling the guy and wanting to hold onto their realtionship. They broke up and later on, the guy is the one making all the calls, and trying to talk to the girl but now they're talking about telling him that this is how it feels to want to talk to someone who wasn't there and for calling someone who never picked up his call. This is how it feels when you want someone you can't have. The girl has moved on and is just watching her phone ring with is number on it, but ignores it.
:)