If I have done anything right, it was when I removed the temptation of W's facebook. It has brought me a lot of peace of mind not snooping. I would suggest you remove him on all your social media, for your own sanity. It's a lot harder to snoop when those things aren't options.
My W had to create a new fb account for all of her nonsense as well, she keeps it very private and only invites people that are accepting of her A to it. On her older fb account, she is still married. Can't make heads or tails of what they're doing and it is far easier if you remove yourself from it.
M: 38 W: 37 T: 20 M: 19 Kids: Stepson?20, S19, S16, D12 BD: 02/19/2015 (She moved out) PA Confirmed: 02/22/2015 (She is now living with OM) Dazed and confused: 09/13/2015