Scully in “The Rain King”

Scully

(about Sheila and Holman) Well, it seems to me that the best relationships - the ones that last - are frequently the ones that are rooted in friendship. You know, one day you look at the person and you see something more than you did the night before. Like a switch has been flicked somewhere. And the person who was just a friend is... suddenly the only person you can ever imagine yourself with. (seems to realize she could be talking about herself and Mulder)