I wrote this many years ago, and since I was on vacation the week of Va'eschanan and didn't have the time to write something new, I present this from waaaaay back.
Parshat Va'etchanan
by Rabbi Avi Billet
The Talmud (Taanit 30b) quotes the mishnah when it says there were no holidays (literally "good days") on the Jewish calendar as great as the 15th of Av and Yom Kippur. The Talmud delves into the greatness of the 15th of Av (which falls this year on Shabbat), famously describing how single girls would dance in the fields and single men would meet them in the greatest singles events of all times.
It's a strange turnaround from Tisha B'Av, the saddest day on the calendar, which we observed 6 days ago. How could we have such a drastic change?
We can look to the haftarah – Nachamu Ami – "be comforted, My people" because things will change. Things will get better.
But perhaps we can find even greater inspiration from the parsha itself.