Hi Alisha,
I'm sorry to hear of your brother's current situation. I think ANY drug can ruin lives, including weed.
Addiction is a complex beast of genetics, environment, timing and current situation/mindset to name a few co-existences for the beast of addiction to rear it's ugly head.
If the silver bullet existed, addiction would be obsolete for all substances, including alcohol.
Any drug isn't the cause for addiction but the symptom of underlying issues that need to be rectified for those suffering to heal.
Hope your brother finds the solution and can get back to a better path in life.