I agree with sainoran, the ibuprofen has the potential to do great damage . I think you would be better trying to taper off pure codeine if you can get some?
Your GP might be more sympathetic than you think they may be and could maybe come up with a taper plan for you.
I know how awful the withdrawals are, I was on df118 for about 19 years for chronic pain and came off them recently by tapering over a few months and it was one of the most difficult things I’ve ever done, but I’m starting to see the light at the end of the tunnel now having been off them for nearly 4 weeks, and so will you in time. The symptoms you are getting do sound like withdrawals, both the physical ones snd the depression. I totally know where you are coming from when you say you don’t have any interest in stuff and don’t want to see anyone. I pretty much hid from even some of my closest family as I didn’t want anyone seeing me with drawing and had nothing of interest to talk about as I had just been stuck at home trying to get through each day ( and hellish restless night) l look back over the last year and think how the f*** did I get through that?
Just concentrate on getting through each day and you will get there in the end. Things do get better and the withdrawals won’t last forever.