If you have used addictive substances for a long time, it is best to stop in consultation with your doctor. Together with your doctor, you can look at the best way to cut back the use. This will sometimes be by reducing the substance. Or the doctor may choose to give you a substance that is not so strong. If somebody stops at once, the old complaints can come back. These are sometimes worse than before. You become more anxious or restless and sleep worse again. The risk is that you start to use again. When you realize in advance that the complaints can come back, you accept this and if you are willing to tolerate it, the recovery will go faster. Never try to stop just before some exciting or emotional event. In that case, it is better to wait for a quieter period. You may not succeed to stop at once and could fall back. Don't give up, and try to figure out why this setback happened. Determine how you could react differently in the same situation next time, for example, by doing relaxation exercises.
If all this doesn't work, your doctor can always refer you to a drug treatment institution.