Jessie James Decker discusses mental illness.

The 34-year-old singer posted about anxiety and despair on Instagram. Decker has fought with it "these last years."

"It's up-and-down. There have been really beautiful, amazing moments but also some pretty low lows," Decker said. 

The reason why I want to share this is because I think I got to a place where I was trying to hide my vulnerabilities because if I made everything look great all the time it would hide my internal struggles. 

I have also always felt a duty to make people smile and happy or laugh and always be that bubbly girl. 

I have a very blessed life with healthy children and an incredible loving tock of a husband.  

But I have definitely struggled these past couple years. My anxiety has gotten worse, my self-esteem, my confidence 

Decker, who married NFL player Eric Decker in 2013, said she has "body image issues" and sometimes "cries."