"I've found that in my own life crisis God has drawn near to me ("He's near to the brokenhearted" Psalms 34:18) and my faith has been more precious to me than ever before," Anna said.
"Many have asked how I am doing. So many have asked that its actually humbling and touching. 2015 was the most difficult year of my life," she wrote, referencing Josh's controversies, including his public confession to being addicted to pornography and to being unfaithful to Anna, as well as the 2006 accusation that he inappropriately touched five minor girls (two of whom were his younger sisters Jill Dillard and Jessa Seewald) as a teenager, which was brought to light in 2015.
Josh checked into a faith-based rehabilitation center in Rockford, Illinois, last year to receive treatment following his porn confession.
Josh Duggar Checks into Rehab, Starts 'A Long Journey Toward Wholeness and Recovery'
"Just recently I visited Josh," Anna wrote. "It was an important step on a long difficult road." (A source previously told PEOPLE Anna took their youngest daughter, Meredith Grace, to visit Josh as well.)
"I want to thank all of you for your prayers and your messages of hope," Anna wrote. "I can never express how your kindness and prayers have brought encouragement when I needed it most – outpacing the grief and discouragement at every turn."
In fact, the former 19 Kids and Counting star was all smiles during a recent shopping trip with her sisters-in-law on Friday.
Source: The Duggar Family / Facebook
"Please continue to pray for me, Josh and our children."