Can massage help you lose weight? The simple answer is no, massage alone will not help you lose weight. That being said if you incorporate massage into your budding healthy lifestyle, it CAN keep you motivated, reduce muscle soreness from exercise, tone the body so all the effort is seen more clearly, reduced stress and anxiety (a major factor in gaining weight or staying overweight is stress and stress eating). So massage is something you should incorporate into your life.
How often? that really depends on your budget but if you get a massage anywhere from once a month to once a week you will see the benefits. Getting one every months is not enough.