I'm not too sure Widmore is behind the fake 815 crash, remember how the helicopter pilot whose name I can't think of right at this moment had made a call and said he was suppose to be the pilot on flight 815. And perhaps what information he knew had drawn Widmore attention into finding the real black box. Of course Ben's has eyes on Widmore and learns that Widmore is looking for the real crash site, puts Micheal on the ship. So the freighter does find the real black box and decide to have the helicopter go to the island to find any surviours, lo behold they do find some.
There's got to be some kind of history between Ben and Widmore maybe the girl who Ben was so in love with is related to Widmore and was kidnap with some other family memebers and brought to the island. And Widmore has made it his duty to find the island to find her.
I don't know I'm sure somewhere we'll find out what the deal is between the two evils.

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Standing in the ocean with the sun burning low in the west
Like a fire in the cavernous darkness at the heart of the beast
With my beliefs and possessions, stopped at the frontier in my chest
At the edge of my country, my back to the sea, looking east