There is also a sort of combo of biology/personality who is easier addicted than others. For biology, look at the ravages "firewater" brought to the American Indian population. For personality or personal type of addiction, look to the depressed or disthymic or bipolar population. They are far more tempted to self-medicate than a person blessed with a stable neurology.
Since Rush had trouble with alcohol in his past, as well as depression, he will need to rely on things other than medication to keep him stable. It will require some creativity and willpower on his part.
If his drug abuse kept his weight down, he will also have a hard time there, as food might be the only thing left to indulge in. I don't think it will be easy, but in G-d all things are possible.
There is also a sort of combo of biology/personality who is easier addicted than others. For biology, look at the ravages "firewater" brought to the American Indian population. For personality or personal type of addiction, look to the depressed or disthymic or bipolar population. They are far more tempted to self-medicate than a person blessed with a stable neurology. Yes, but the Drug Warriors don't care. A large part of their psychology is the need to feel morally superior to others. They get a thrill out of condemning drug addicts as "morally weak" and sending them to prison. Somehow, this makes the Drug Warriors feel better about themselves.