You were walking down the street, nothing was unusual and then suddenly she came out from a nearby shop and it happened that you fell in love with her at the first sight! Huhh!! What happened?!!
The answer is simple, its all related to how your mind works. If you are single or currently not in a relationship then your mind will always be on a hunt for your long awaited partner. Even if you think that you don't care about relationships now still you will fall in love with the first person who matches your criteria.