This may sound a bit odd, but I left my cat at a friends place (who has 2 cats) for about a week, while visiting her very often (almost every day). She came home and all of a sudden picked up this licking habit. When I am about to wake up she'll come lay on my chest (which I've trained her to do) but then she'll start licking my face! She never did this before. Has anyone else experienced this?