If Aizen gets into Izanami's Genjutsu, will he be able to break out of it? Or will it stay in it forever?

Aizen already accepted himself at the end of the manga. That was the point of the last speech of the series been Aizen talking and understanding humans instead of wishing to become a God of gods. That move doesn't work on people who already accepted themselves.

Hogyoku would warp reality and break him out of it.

Pretty much what ryuuzakiscorpio said

@lexa59: it's only effective on narcissists like kabuto. Aizen has already came to his resolve so it wont be affective

No, it won't work on Aizen.

Aizen accepts himself.

Assuming it works on Aizen. Aizen would break out of it.

Him getting over his god complex means nothing againts a genutsu that will repeatedly told him to get over his mistakes, Izanami works more in a way to turno people into morally right persons anything. And Aizen isn't an one even in the end of series.

Ain't breaking shit

Had to adapt to a far weaker illusion ability instead of breaking it lmao