In the Times, Emily Kelly tells us about her husband, a former football player who took a lot of blows to the head.

Professional football is a brutal sport, he knew that. But he loved it anyway. And he accepted the risks of bruises and broken bones. What he didn’t know was that along with a battered body can come a battered mind.

For decades, it was not well understood that football can permanently harm the brain. Otherwise, many parents would most likely not have signed their boys up to play. But this reality was obscured by the N.F.L.’s top medical experts, who for years had denied any link between the sport and long-term degenerative brain diseases like chronic traumatic encephalopathy.

Just as tobacco companies for years denied any link between tobacco and lung cancer.

That started to change in late 2009 when, for the first time, the N.F.L. publicly acknowledged that concussions can have long-term effects. In 2016, a top league official admitted that there is a connection between football and C.T.E., which has now been found in the brains of more than 100 deceased players. But for Rob, and countless other players, those admissions came too late.

And yet – people here still get wildly excited about football and expect everyone else to share their enthusiasm. I find that disturbing.

It wasn’t until I joined a private Facebook group of more than 2,400 women, all connected in some way to current or former N.F.L. players, that I realized I wasn’t alone.

Our stories are eerily similar, our loved ones’ symptoms almost identical: the bizarre behavior I had tried to ignore, the obsessive laundering of old clothes — our washing machine ran from morning till night.

It was comforting and terrifying all at the same time. Why did so many of us see the same strange behaviors? “Our neurologist said they do it to calm their brains,” one friend told me.

Symptoms consistent with C.T.E. are a recurring topic in the Facebook group. They include memory loss, confusion, impaired judgment, aggression, depression and anxiety. These problems become apparent sometimes years or even decades after a player hangs up his helmet.

One woman may write a post, desperate and afraid of the man her husband is becoming — the rage, mood swings, depression, memory loss. A man so drastically different from the one she once knew. Hundreds of comments will follow, woman after woman confirming that she is going through the exact same thing.

While the symptoms and behaviors are telling, C.T.E. can be conclusively diagnosed only posthumously, because it requires the close examination of brain tissue. But many of us, including me, are convinced our husbands suffer from the disease. We try to comfort one another with the same words: “Just know you’re not alone.”

I don’t think the public has any idea how widespread this problem truly is. Rob and I hope that, in telling our story, we might help other families. There are likely to be hundreds of wives and partners of football players, maybe more, who live a life like mine. Sadly, there is a feeling of shame among those affected, in both the men and their families.

But hey, the Super Bowl is tomorrow. Let’s focus on that instead.