sarah owen , 21 , was attacked by her boyfriend preston wright , 23 , with a knife , then turned the weapon on himself at a house in oklahoma .
preston wright , 23 , killed his girlfriend , sarah owen , 21 , after he stabbed her several times with a knife then turned the weapon on himself at a house in oklahoma .
the couple began arguing on the porch for a while before she was allowed into the garage to remove some things .