Need help steering box? Car out of commission

Manual or power steering, I'm guessing power.
If you've had 2 alignments done and the steering wheel is 45* off, that's a problem. Sounds like you may have a box issue, but you'll need to verify exactly where the "slack" is.
I'm rephrasing this to make sure I understand the issue. When you are holding the wheel at 45* you have taken the slack out in one direction, as soon as you hit a bump, the tires kick the slack to the opposite steering gear face or tie rod ends and you have to yank the wheel to take up the slack and bring it back straight

You can check the play by turning the steering wheel and see how far it moves before turning the tires.

Method: Hood up, drivers window open, engine off, steering wheel unlocked. ( with the engine off the tires wont want to move but if there is play in the box, you will be able to identify it ) Reach through the window and turn the wheel while standing outside of the car. If the steering wheel moves more than "a little", it will need to be replaced or rebuilt.

You can also test this by grabbing the steering coupler in the engine bay and turning it by hand. This will tell if the play is in the box or tie rods (if you can see the centerlink move with the pitman arm.
As for rebuilding the box, I've done some pretty in depth repairs before but I don't think I would attempt to rebuild it. Too many variables like gear depth and preload and things on something as important as steering, but maybe I'm just a wuss. :)