I had the same problem. I gained like 30 pounds over the first year and I have always been super skinny. I was constantly eating, snacking, anything in sight. I started doing all kinds of diet and exercise and nothing would help me shed the weight, instead I just got more hungry. Only in the last probably 4 months have a started to shed some pounds

The worst part of the recovery though was that I had to get hormone treatments about a year in cause my testosterone levels dropped like mad (current theory it was a combination of the withdrawal and weight gain). I was sleeping all the time and groggy all the rest and I had no motivation for anything it sucked