I think you're mixing your apples and oranges. You've most likely been in some level of depression since you found out about the cancer. It's one of BIG SCARY's, and the depression doesn't just disappear when you end your treatment, especially if there are complications (nerve damage). I'm sure you just wanted to put the whole experience behind you and get on with your life, but just quitting your meds, especially narcotics, cold turkey throws your hole system into chaos. That's why you were scheduled to do it over a slower amount of time.
I was cut off narcotic meds (which I took for migraines) cold turkey, so I can understand. However, the difference is that I was also taking medication for depression, which was not changed.
The added depression you are feeling is probably still withdrawal from the medication. By mentioning going back on the meds for the depression, it will just numb you out again, and that is just going to slow down the depressive thoughts and won't do anything for your depression long term. You need to talk with your doctor immediately, tell him what you did, and see if you should go back on your narcotics for a while, and possibly start taking some kind of anti-depressant(s).
The mental/emotional effects of having cancer last a long time past the time your body takes to heal. Nerve damage may be permanent, which is something you may just have to adjust to. You may always have to take some kind of medication for it, and have to accept that fact.
Try to concentrate on the fact that the cancer was caught early enough to treat, and you have been given a new lease on life. So many people aren't that lucky. Count your blessings, and take your meds if you need to.
Remember, we are always here for you, even if you just need to vent. Let us know how you are doing.
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