For me depression was a big part of PAWS and getting off of opiates in general and didn't have much to do with Subs / Nalox since when I was on that or nothing at all I still experienced depression.
I think you said you are already on antidepressants, but if not might be a good thing to bring up with your doctor OR maybe try some other antidepressant. It is really a crap shoot when it comes to antidepressants. Psych doctors basically just give you it and say see how you feel. Sometimes not much rhyme or reason to which one works best and is a case by case basis.
As always I recommend trying to get some light exercise if possible. Getting proper sleep and eating right. All of the little things can add up to big things. It took me a good year before I felt like my brain was firing normally again. Sucks because getting clean is hard enough without feeling like there is no reason to live some days. Feels like ground hog day sometimes. Every day sucks and you think you are never going to be happy again. Just keep trudging ahead and it will come around. Good luck and take care!!