Has anybody else had DD stomach cramps for over 3 months?

Hi new to this my dad is the sufferer he has constant pain unfortunately he was put on oxi CODINE so is now addicted as well as having DD. He is mis using this pain relief so on top of everything else goes cold turkey with no pain relief at all for at least one to two days a week. Doctor says he is doing more than he should for him which means an appointment at the surgery every other week on the day after he picks up his weekly prescription. Dad's diet is terrible and he chain smokes in top of this my mum dies of lung cancer a year ago so depression is playing a part. I cannot get any help for him the doctor just does not want to know he offers help supposedly and my dad supposedly is turning it down. What can I do for him he is refusing to come off of the codine so therefore has been signed off from the drug counserlours I am so frustrated and now realise it is a much bigger problem as there are so many more people in constant pain this cannot be right!