First of all, name change as I have other friends who read these boards religiously and may make links to this.
So, I work in IT and a good friend of mine of 26 years asked me to look at her husband's laptop while he's "away on business" as it's been developing issues. As far as I know he's aware of this, but I'm not certain. She dropped it off to me the other night and as I ended up with an unexpected day off, I've been working on it but as part of sorting the issues have discovered he's a member of a dating/hook-up website called "ABF Heaven". I'd never heard of it but this site is to find people who share the kink/fetish of "adult breastfeeding" and from the messages he's been exchanging it appears he's been meeting women all over the country to indulge this fetish. It also looks like that is where he actually is away now, staying a whole week with a woman he's never met before, 200 miles away "to suckle night and day". He must also log in to his account on this site on his phone as there's been activity while I've had his laptop and it's his most visited page after Google, which is how I found it so easy when dealing with the problems.
I've never liked him personally though on top show we get along fine. They have 4 children, the youngest of which is 3 months old (and ironically being breastfed) and the oldest of which is only 9, so it will be catastrophic for her to discover this. I really don't want to tell her but I feel like I should. To me this is not only cheating but if he's being breastfed by lactating women, I'm sure there's an STD risk too. I'm sure it's only a matter of time before he's having sex with these women too, if not already.
In the meantime, I've taken and saved screenshots of everything he's been doing so she can have it as evidence in any (very likely) future proceedings. I had to back up all his data as part of the repairs so I know this could be helpful for her too.
As a good friend I feel I have to tell her what I know and as gently as possible. I'm not married but I'd want to know in her position. I'd like to know if this was you, would you want to be told too? I'm considering returning his laptop and advising him that I know what he's up to and say giving him 7 days to tell her and come clean or I will have to do it for him.
What does everyone else think? I've felt sick about this all day. Thanks in advance for your responses.