dangers of gastric bypass surgery ?

My boyfriend is 58 ,was  healthy and fit all his life till 7 yrs. ago. Bad divorce , lots of stress. Now has metabolic syndrome, weighs 285. His brother recently had gastric bypass, almost died, in ICU for 10 days. ( weighed 400 lbs. ) My friend wants a quick fix too . I am begging him to do diet and exercise. He is not motivated, just complains about his condition. 2 months later His brother now eats nothing but baby food and  has lost 70 lbs. I Have heard fears of osteoporosis, muscle loss with this surgery.  What are long term risks of this surgery and can you guide me to a  resource that will help me motivate David  to lose weight naturally and not have this risky, life altering , dangerous surgery ??? please help me help him !!