[Chris85]

I think she became a businesswoman who focuses on earning money by constant touring. Maybe because she knows that there's only so much time left before she becomes completely deaf. Maybe she also wants to enjoy fans' attention while she still can get it. I feel it's a about putting on a show and making money. It's not about music IMO. When you care about music, you take singing lessons, you try to improve your singing skills. I haven't seen any improvement for years to be honest. It's all about visuals and theatrics.
As for making new songs, I've stated this before, she has written tons of lyrics. Maybe she reached the point she no longer has something new to say, at least on a regular basis. She doesn't HAVE to release anything, it's not like she has a contract between her and her fans.
I wouldn't call her lazy, she's always proven to be a hardworking person. Maybe she's just not invested in some things fans expect from her.