has been open about his battle with drug addiction in the past, but has not talked about his mental health battle.Posting a moving video in Instagram, he said he had decided to speak out as he has become involved with new charity It’s OK Not To Be OK..View this post on InstagramDay told fans: “It is well documented out there that I am in recovery from addiction issues and I have spoken about that publicly. “Something I have never spoken about publicly is my mental health issues.”“Some parts of my life have been unbearable until I got to the point where I reached out for help,” said the star.“Today I am choosing to talk about it because I have become involved with this wonderful charity: It’s OK Not To Be OK.”Day said the charity was set up.