I'm honestly not sure about the first. He's there to endorse a whiskey so it would be odd for him to say that it is successfully helping him to forget, unless that's what the makers of the whiskey want it to do. However, I also think it's the most likely meaning.
"Down to sixteen and change" - they started off talking about being married for 25 years. Then Bob points out that you sleep for one-third of your life, so for 8 years of those 25 years, you're asleep. That leaves just over 16 years to account for (actually, it leaves 17 years to account for but I guess some poetic licence was used). When we calculate a subtraction, we use "down to". 25 years minus 8 years means you're down to 17 years. Take away another 7 years and you're down to 10 years.
Student or Learner