OP, everyone will tell you that my ex is a lovely bloke, really nice, great dad. What they won't tell you is that he beat the shit out of me, threatened to kill our DC, and told everyone who'd listen that I'd had an affair (I hadn't). They won't tell you he'd racked up debts of £30k that I knew nothing about.They also won't tell you that within a month of our 16yr relationship ending he'd started seeing someone new. They also won't tell you he didn't pay CM for nine months until I applied for it, and he lied to avoid paying his due. They won't tell you that the DC & I were on the verge on being made homeless because of him. They also won't tell you how I tried to hide everything from friends and family whilst he told everyone how evil I was, so I had no support or anyone to rely on, so I had to lie and say my statement to the Police was wrong, just to get charges dropped, in order to get some help from my family. They won't tell you that, because they don't know it, because he's such a great bloke, and has never done anything wrong, and it's me that's the problem...
He still sees his children regularly. They have a stepmother now - someone I've never met, who's undoubtedly been given his narrative, and has views on the type of person I am. I am not in any way comfortable with my children spending time in that environment, mostly because it's obviously upsetting for them, but also wondering what's said about me, and how my DC feel about it. On the nights they're not with me, I cry. But I have to live with it, because I know it's in their best interests to have a relationship with their dad.
If I can do that, then I wonder what it is that your close friend has done that means he's been content to live for six years without even seeing his child.