In keeping with the newly proposed rules, I just want to say first that there was no animosity intended in the title toward Hillary or any of her supporters. And according to some of the exit polls, there should be a sizable number of her supporters that actually agree with it. 
But to the point, an enormous amount of money has been donated and spent on a campaign that most everyone agrees can only have one logical outcome. After all of the smears and fears, Obama is still solidly positioned to win in every important category - delegates, popular vote, number of states, and money raised. The best Hillary can do, considering the most favorable scenario possible for her, is a close second. 
I've always tried to see facts as they were and to face reality early. I'm not one to exert a great deal of energy into something that has a near-zero chance of success. There's a certain principle known as the point of diminishing returns that any good businessperson understands. And despite the benefits of "toughening up Obama for the general," I think we are well past that point. 
Though I'm sure this is all very difficult for her supporters to accept, it is what it is. Her continued fight in this campaign will burn up precious financial resources and further exasperate the recent rift in the party only to prove that yes she can finish in a close second.