Kelly, I don't think there's anything particularly obtuse about it, and I DEFINITELY don't think it has anything to do with "jealousy of (Carla's) looks"...
Carla, I don't know your wife, but I would suggest you consider that that picture and your relationship with your "dressing" and your self when "dressed" represent what she feels she has to compete with for your attention, time, energy, and desire. If she feels that way, there's a good chance that your behavior is what's making her feel that way.
Do you have a picture of HER on your desktop too?