To begin, I don't know where so many Christian people picked up the awful habit of using "just" as a modifier to everything.
"Lord, we just thank you for this and that."

"God, we just praise your name for..."

"Jesus, we just pray for the sick and hurting folk among us."

Just give up a few of those "justs" already! It's as aggravating to people who are reasonably comfortable with English as the myriad "you knows" a professional athlete weaves into a 30-second interview.

Ax-grinding and pet peeve aside for now, the lady on camera from Oklahoma shook her head and looked into the interviewer's eyes. "It was just God's will that I was spared when the tornado hit," she said. "The Bible says 'everything happens for a reason,' and I believe that. I believe it now more than ever."

For starters, the Bible most assuredly does not say that everything happens for a reason. To the contrary, the Bible says there is a great deal of randomness in human experience. For example, these words from Jesus:

"He causes his sun to rise on the evil and the good, and sends rain on the righteous and the unrighteous" (Matthew 5:45 NIV).

If there was a one-to-one relationship between good people and good outcomes on the one hand and bad people and bad experiences on the other, we would be hard pressed to explain the stories of Job, Jesus, and Christian martyrs. That good people don't get a pass on pain is as it must be. Otherwise, we would all be Christians just to avoid bankruptcy, cancer, or tornadoes.

And what of the two dozen who died? Especially the children? Or the dead and wounded from the Boston bombing? Or the British soldier murdered on the street? Were those events and their outcomes "just God's will" too? Small comfort that! To believe these things were God's will would motivate most of us either to atheism or to faith in a God who is more to be dreaded than loved.

Not everything that happens in this world is God's will by any means.
I don't think people such as the lady on TV mean harm. In fact, I am quite sure they mean to be saying something pious and affirming. They are trying to lean into their faith to deal with unimaginable shock. They are attempting to express gratitude for being alive and to acknowledge their faith in God.

Perhaps it is better simply to say we don't know why certain horrible (or wonderful!) things happen in our world... to confess our fears and confusion... to accept good fortune with a view toward using it to help others as well as self.

Not everything that happens in this world is God's will by any means. But, in everything that happens, we can seek God's will by continuing to trust, being faithful to what we know is right, and encouraging others to do the same. And we can do this because of this promise:

And we know that God causes everything to work together for the good of those who love him and are called according to his purpose (Romans 8:28).