I think people are just trying to help and to be honest your original post is a bit hard to follow that your able to move into different departments with in the same company, most people don't have an option like that.

I would "guess" that most everyone here has been in horrible working situations at some point or another and maybe that is the reason you have gotten a few " quit your job and find a better one" type replies.

Personally I think going back to day shift regardless of what department your in is going to be a huge step in the right direction.

All this is just my opinion of course, I just hope that you can find some peace and rest when it comes to you working situation.