My friend's husband left her for another woman, and she asked God "Why?"
It took her months to realize that it was her husband's choice, not God's. We sometimes do that--blame God for people's sins.
We know God is all powerful, but we forget He's also all good, all wise, and all knowing. We only see a part of the picture and God sees it all (1 Corinthians 13:12).
"For my thoughts are not your thoughts, neither are your ways my ways,” declares the Lord. “As the heavens are higher than the earth, so are my ways higher than your ways and my thoughts than your thoughts." Isaiah 55:8-11
But that passage doesn't end there. God goes on to promise that He'll accomplish His desires and purposes (Isaiah 55:8-11). We can rest confidently in that.