For me... when I'm tempted to have a drink to take the edge off my anxiety over either complicated riffs or solo parts I've found to address & face the anxiety as a motivator to practice more works better. After the performance the sense of accomplishment is rewarding which reinforces the next time anxiety comes. Again, this is the method that works for me.
It could TOTALLY be anxiety driven. This band is math-y so maybe that’s an unconscious thing too.
Just to clarify, I’m not talking about being wasted while playing. Usually no more than 3 over a four hour period. Still has an impact though.