Your reason, your motivation has to be yours, for you and about you. You already are a good mother, don't create a bad mother image to try and motivate yourself.
It should be benefits, things you enjoy about being slim, often the opposite of what experience with being overweight. Nicer close for the smaller figures become accessible. More room in the seats at the movies. Not as tired walking, can keep up with the kids and the dog when they play. Can play with them more actively. More flexibility.
List what you would enjoy about being slim.
Alex
