Unfortunately, a specific time frame cannot be set for you to feel normal again; after using methodone for so long. Those who use it on short term can have a guess but those who were on long term- it takes a very long time. Some say 1 and 4 months; others say 2 years; while others say that the time frame can even be more.
Now that the drug is gone; you will see the difference and the difference is the reality of life where you will have to have your own energy reserves from your body to get on with your day, rely on your own emotional state and so on. Without the drug and the hardships of life; there might be a temptation to go back.
What I would recommend is to get the vitamin D injections since most people are vitamin D deficient. This vitamin D gives mental alertness and calmness in a safe, natural and nonaddictive way. Also, either B12 or B complex injections help out a lot in mood, emotions, digestion, concentration and energy.
The B12 or B complex along with the vitam D can be an inmerse resource for your situation. But I must say that it must injections because pills or liquid of the B or D vitamins take long to take effect and they might either work or not work at all. Also, the B complex is better than the B12 but the B complex injection is naturally painful.
Try CBD Oil non-addicting and they say it is good to kick Opiates with. You can get it on-line
IMO...what your looking for is recovery. You've gone through the physical part of w/d, now it's time to go through the mind f**k that is going on in your head. Recovery, i.e., N/A, A/A, Celebrate Recovery, is where you will get relief for what your going through. It IS for everybody, but not everyone is interested, so it's on you to decide. I'm not into pushing anyone into recovery, however, I w/d off of suboxone after taking 24mg a day for 7 years. I quit cold turkey Jan 1st, 2014 and have been clean ever since...4 years and 3 months. I had a very similar timeline to yours, 3 months of physical w/d and I felt like a wet noodle for months after that. What helped TREMENDOUSLY was finding recovery. Eating healthy, exercising, getting regular sleep, meditation, all help as well...but getting to the root of your issues will help more!
Good luck to you.