Force cannot make the addict remain in treatment but loving family members like wife and children can talk to him affectionately without showing any sign of the resentment they might feel for causing so much anguish to all of them. There is nothing like love and affection, which can move any person mentally and the addict is no exception. A lot of persuasions with kind words can only help in this matter. The person will remain in treatment so long as the atmosphere around him is full of love and affection, and he feels like a useful member of the family.
The key element in keeping the patient in treatment is not to provoke him with unkind words, though the temptation might be great because of the suffering. Patience, understanding, the welfare of the family, and the good of the patient, etc. are all matters that will help in making the patient remain in treatment so that he transforms himself into a useful member of society.