"The Talmud explains that the month of Tevet was a particularly opportune time, since the cold causes “the body to take pleasure from the body [of another].”" (source)

"The month of Tevet is one of the darker, lowly months of the year." (source)

"Although dark and difficult, Tevet is your opportunity to grow." (source)

"With the exception of the closing days of Chanukah, the month of Tevet contains no Yom Tov or festive day." (source)