I wanted to know how to clean off glaze that has appeared on the outside front windshield. (Yes I have searched already)

I believe this has appeared after I used Rain X about 2 month ago. Now, I have a glaze on some parts of the window and some parts do not have a glaze. This is irking me since when I drive in the rain at night, the head light from the opposing direction makes me have a tough time looking through my window due to the semi-glaze that appears on the window. Does any one know how to remove the rain-x and the glaze off the window?

Things I have done to remove the glaze:
1) Regular car wash with car soap
2) Used windex and newspaper
3) Washed only the window with kitchen detergent (thought it might be grease)
4) Used windex, paper towel and some tough scrubbing

Does anybody know if ammonia is good or bad for the windshield? (I read links telling me good and bad so now I'm confused if its good or bad).

If anybody has a good home made formula please share it with me.
Thanks