The former world No. 7 illuminates mental illness for the Bell Let's Talk campaign. (Getty)

As January came to a close, retired tennis star and commentator Mardy Fish made his entry in the annual Bell Let's Talk initiative that highlights mental-health issues. 

"Ever since I was diagnosed with severe anxiety disorder I have tried not to judge people," Fish wrote, in part, on Twitter. "You never know what someone is going through or the reasons why people do things."

Fish rather openly struggled with anxiety late in his professional playing career, withdrawing from a 2012 US Open quarterfinal match against Roger Federer due to the condition. He retired in 2015.  

His post and others from celebrities and everyday citizens led to over 130 million posts on social media channels using the #BellLetsTalk hashtag. Shania Twain, Canadian prime minister Justin Trudeau, Celine Dion, William Shatner, Alessia Cara and Fifth Harmony were among the other notables who published thoughts about related issues during the Canada-centric campaign. 

As a result, Bell, the Montreal-based telecom company, made its own donation toward mental-health treatment and more, and nearly $7 million has been raised to date overall. 

This social push has proven to have quite the legs, so to speak, with talk about mental-health matters extending for a few days across a range of sectors–sports, entertainment, academia and more.

Anxiety. Depression. Impostor syndrome. These and other conditions can be crippling in emotional, social and other ways for those who cope with them. Luckily, the likes of Fish and many others pull back the veil on not just one but most every day of the year.

Follow Jon on Twitter @jonscott9