Fascinating Tzemach Tzedek Midrash Yeshayahu cured harsh prophecies of Yirmiahu.

The revealed side of G-d is hidden during Golas. The healing cure comes with the Geulah, the redemption. There is a connection between the hidden and the revealed side of Hashem through the Yud k, Vov k. Hence, by the harsh prophicies of Yirmiahu the Tzemach Tzedek reveals how we can have a refua.