He's on vacation, and then Thom said last night it was his honeymoon. I think he was kidding, maybe it's a 2nd honeymoon kinda thing. Or he is suspended, I don't really know...
He is still married to Amanda Ingram, at least I think?
As far as working, I think Marty has just made a decision to work less (do what he wants while he still can), he will turn 70 this month.
I don't think Scully travels anymore, unless it's to San Diego or San Fran.