Around this time last year someone was wondering whether she was in love with a person or an idea of that person. That stuck in my brain, and continues to as my own inner Wembley constantly questions and deconstructs my affections for certain people. What I would suggest is that everyone is always in love with their idea of a person, to some extent. Non-telepathic beings that we are, we never fully, truly know each other. There are always secrets that can be held back; a wife can live decades with her husband and have no idea about his latex boot fetish. What we know of a person is dependent upon our experiences with them, who they are around us, and that’s an inherently limited array of data. 
This is particularly the case in the early stages of a romance. When we know very little about a person, we build on what we know of them and what our imaginations would like them to be. In the case of a person for whom we have great affection, our imaginations tend to assume that this person is worthy of higher esteem than perhaps they deserve. When someone excites us romantically, our brains get excited and fill in the gaps with appealing assumptions. We idealize and in some cases idolize. Then when the relationship doesn’t last, we mourn not only the loss of a physical and emotional presence, but also the loss of the ideal that we held onto so strongly.
I try to puzzle out these sorts of things so that I can avoid them in the future, but in this case I don’t think there’s any way to avoid it. Our brains are geared to imagine and create and run scenarios. Creating and losing our own illusions may be unavoidable. Hopefully by simply being aware of these dynamics, we can proceed more cautiously and cushion the inevitable disappointments. The alternative is to get incredibly excited about someone you barely know and then get incredibly depressed when they don’t meet your expectations.
I’d be a terrible romatic comedy screenwriter.
1.) I also have this theory that everyone is a different person to each of their friends. The person I am when I’m with Friend A is a different person from the one I am with Friend B. The differences are subtle, but very real. My mental filters change, my movements and statements are different and obviously our exchanges will be specific to our shared interests and experiences. When we connect, we change slightly.