I’m playing NHL 2K8 on my Xbox 380 and I don’t get it: An NHL game can’t end in a tie, like 3-3–one point each–or what?
They can’t anymore; a few years ago they could. Wherdja get a Xbox 380? 
All NHL games that end overtime tied now go to a “shootout” where each team takes three penalty shots, alternating. The team that scores the most wins. The team that loses the shootout gets only one point for the tie at the end of regulation. Winners in overtime get the same bonus point.
One regulation time ends, each team is guaranteed 1 point. The winner of the OT period or via the shootout gets 2 points in the standings.
Let’s make sure we’re answering the OP’s actual question, which is how an NHL game can end in a tie. This should not be happening in NHL 2K8, which p0resumably was made long after the shootout was instituted, unless it has an option to turn the shootout rule off and on.