There was the case a few years ago with the young wife and mother of a baby who up and left with a man she had met at the 7/11. Did not take the baby, did not leave a note, in fact she left her car in a park with the driver's door hanging open, as if she had been pulled out. Her name was Tara T-something...can't recall her last name. Eventually she and the boyfriend were tracked to Florida, found in a beachside motel.
I am always reminded of her case (not the only one surely) when people say a mother would never leave her children...they do, via suicides or running away. Not saying this is such a case, but it can't be ruled out. Jmo