I agree, Kaffe. I've never used FB to talk about details of our separation and all, just random stuff like "Going through challenging patch, please pray" or something like that. The only time I made a distinct indication of what's going on is when I first joined FB back in 12/10 - I changed my relationship status to 'Separated'. And my wife, at that point, still had her status as 'Married'. When she noticed my new status, she changed hers too.
In terms of my thoughts on putting a 'Relationship Ended' date on my Timeline (which I won't, BTW), I can't remember who in this forum instilled in me earlier on that I have to face the fact that THIS marriage is dead, so why not be honest about it? That's what I tell my friend and family or anybody I talk to -- that I'm not out to save this marriage in the traditional sense, because if my wife and I do decided to work together again, it would be from scratch. Take the good, remember the old and build on that.