Ex boyfriend suicidal over me

Hi All.
I recently got married a month a half ago to my wonderful husband. Things have been going so well.
Before I found my husband however, I dated this guy for 5 years. Not only did we date, but he was my first love and I his.
We kept up as friends even after breaking up. Things were great! I would never mention the wedding plans or anything to him. He already knew I was engaged to be married and respected that, I didn't need to make it worse by consistently talking about my new guy. We were just friends. 
Flash forward to the week before the wedding and he stops talking me. I totally understand where he is coming from and I respect that he wants to seperate himself from me, as the wedding was causing old feelings and hurt to come up for him. I left him be.
He blocked me on his phone and all social media. I got the hint and decided to not contact him anymore for his own good.
This past weekend I get a call from one of our mutual friends.. She said that my ex unblocked me and was looking at all my pictures.. Most of which were wedding ones that others had posted on my timeline. This mutual friend exclaimed that seeing these photos made my ex realize how much he missed me and was still in love with me.. And that he has become extremely suicidal as of recently. 
She suggested I reach out to him to see if he is ok..
What do I do? I feel as though me reaching out may make things worse.. But I mean we were best friends before and after the break up, so do I reach out and make sure he is ok? I'm conflicted. 
I know him and I know he would never do this for attention.. He is emotionally disturbed and truly could injure himself because of me. I would never forgive myself if he did.
Any suggestions on how to move forward?