Hmmm... sounds iffy that it happened that fast. I would be checking the shaft to determine if there was growth or corrosion
on it inside the cutlass bearing that ate up the inside of the bearing. Especially if the boat
sat a lot after the first replacement.
To check alignment you need to uncouple the shaft and flange from the engine. When you do that and slip it back maybe 1/2" does it align with it's mating half? or does it move up/down/to the side?
However, I will say that there's only so much movement it can transfer to the cutlass as the stuffing box holds it somewhat into place.
So be sure to look at everything else:
-What prop is on it? is it bent?
-If a feathering prop is one blade installed a notch off?
-Corrosion on the shaft as mentioned?