If any of you guys wonder what happened at the end, I'll tell you. After you rescue your wife, she says that she was bit at the hospital. This means she is infected. During the boat ride, they stop. Not because there's no fuel, but because she turned. (signified with the growl at the end) They stop so you (the main character) can end her misery of turning. It's a tragic story where there's no happy ending.