Hey--you and I are at the same point this round!
I know how hard it is to set boundaries. We have alcohol around us all of the time. I have come close but haven't ever become so sure of my sobriety that I can be in the party without drinking. I intend to get there this time though.
So hang in there and do this for yourself.
If your friend needs you to hang out, can you do it at a coffee shop?