It really helps to emphasize her attitude in life. Nothing and nobody is worth the slightest amount of effort on her side. Losing a bit of weight in preparation for the wedding - requires too much willpower, getting out of the scooter to walk down the aisle - that's almost like exercise, putting the cigarette out - why give even the slightest amount of consideration for the person she allegedly loves? Much more convenient to only think of her own immediate needs and wants.