Stay with the protein shakes mate.
I know I've never gotten a hangover from one anyway.(lol)
The path back downhill seems to be everywhere at once and one false step can put you right back where you started.
At an AA meeting last night someone said something like "I know I've got pleanty of drunks left in me but I'm not sure how many recoveries I've got left in me."
This made a lot of sense to me. If something is going to drag you backwards then stay away from it. If it is this hard getting sober this time, how hard will it be next time, and the time after, and the time after that?
Congrats on the sober time and stick with it.
Jig