Why won’t my 2003 Outback motor turnover

My 2003 Outback won’t crank. I’ve replaced the
starter, camshaft sensor and crankshaft sensor. The
starter sounds like it is turning but the engine does
not seem to turn. All pulleys spin with the
serpentine belt when you turn the key as well. It has
the 2.5L 4 cylinder motor in it. It was running fine
when my wife was driving home, then she said it
felt as if she pushed on the brake real hard without
actually doing so and then the car start to
decelerate and when she got to the shoulder it
wouldn’t start.