Yes, I think thirst is a symptom of detox; the body is trying to get rid of the poison. Same thing with sweating. My night sweats were awful at first.
It can be so discouraging when you've let yourself go and have gotten to an unhealthy state. I gained 30 lbs during my last 6 month relapse! All I did was get stoned, eat and sleep it seemed. I was very down on myself.
But empowerment is uplifting. Taking the best care of yourself is uplifting. Just do your best and try not to let the negative feelings take over. Hard to do, I know. I beat myself up pretty badly.
You've had a lot to overcome, a lot of scars. Now you will need to find other ways to sooth yourself besides getting high and eating. Have you looked into counseling or some kind of group therapy?
You are strong, you can do this. Look how far you have come already!
All I can say is GOOD JOB!