You (you in the general sense, that is) don't know what it means to miss a person anymore, after a long while and a half. You feel the feelingness of the missing, like it were gonna build up into it, but then you kind of forget how to get it. How to remember that thing that you miss.
That's weird, because... it's an empty shell of a memory that I miss now, but then where does the impetus come from? And why do I miss a feeling that I can't even remember? In the doorway of my minds eye?
Eyes don't have doors, in a practical sense. Get a grip, Ash.