Sharon has it all (him) under control... All calculated long time ago. Someone clearly needed to save the estate and she has done that fairly well. And a couple of somewhat famous but messed up kids.
A couple months ago she filed for divorce saying that after a couple of years of "sobriety," Ozzy had fallen off the wagon one (again) time too many. I never heard anything after that. I think after she reviewed her finances, she decided she could "suffer" some more.
Jack made a REALLY good documentary, "God Bless Ozzy Osbourne," not too long ago. While you can see the love he has for his parents all over the movie, it's not hard to read between the lines.