I too enjoy drinking alcohol and a few years back went dry for 90 days. I was disappointed. If anything, I felt worse. A clean diet and exercise has much more of an impact on how I feel/sleep than abstaining from alcohol.
Eat less, move more, drink in moderation.
Several studies have shown that exercising improves cognition better than brain training games and activities. Alcohol does impact cognition if it is binge drinking, or you exceed 2+ drinks/day. Though it does take years of drinking for it to be visible.