It was a suicide attempt.  Investigators say the Sunapee man charged in a deadly crash in Lebanon was trying to kill himself when he drove his truck across the median on Interstate 89 in Lebanon, killing a couple and their unborn daughter.   Yesterday, prosecutors said on Saturday, Robert Dellinger recklessly caused the deaths of a Vermont couple when he tried to hit an embankment.  Instead, Dellinger’s truck hit the car Amanda Murphy and Jason Timmons were in.  Dellinger faces 15 to 30 years in prison.