His confidence has been low since his wife cheated on him moved on.
"For whatever we lose, like a you or a me, it's always ourselves we find in the sea" ee cummings
He needs to talk to her about what is bothering him. If he's hurt that there aren't pictures of them as a couple on her FB, he needs to let her know this. If he is hurt that he isn't getting enough of her time or attention or love, he needs to talk to her.
Its good he has you to talk with...encourage him to talk to the person who can do something about the changes he wants...
6-8 months is a decent amount of time, so if he's right, this discussion will possibly end their relationship, but if the alternative is to just pretend all is well, then he's probably better off cutting his losses now.
Above all, be the heroine, not the victim. - Nora Ephron
It is our choices...that show what we truly are, far more than our abilities.
- J. K. Rowling