I will never understand a doctor's concern about someone with CHRONIC pain and their taking of pain medicine. Some people with cancer have terminal chronic pain and MDs still worry about addiction?
There's a big difference between dependence and addiction. The very fact that you can cut back on your medicine means to me that you are not addicted.
Depending upon a medicine to help you live is okay. The stereotype of "addiction" is none of my concern regarding chronic pain...it's CHRONIC pain!
If you can cut back on your medicine, and have pretty much purged your body of it, I don't see why you would continue. Sometimes people with too much medicine, including narcotics etc., need to go in an detox as there is a phenomena where the medicines are causing rebound pain--more pain than you would have with properly managed medicine...
I hope you are discussing this with the doctor who is prescribing your pain medicines. Here in the USA there's been a big crack down by the government and doctors must keep good track. You are doing your MD a disservice by not taking the medicine as prescribed, and they might even find this out through a test and suspect you of selling your pills rather than taking them.
Plus you are not doing yourself any good by not taking your medicine regularly. If you have chronic pain, you need to learn to manage your life with regards to that pain, managing the pain with medicine or whatever... but sometimes taking and sometimes not etc. won't help you manage. Now if you have cut back and it's doing you no harm in your living your life, then maybe you don't need as much medicine. Again, discuss this with your MD as he/she is assuming you are taking it as prescribed.
Take care.