Story wise it made a lot of sense to me, it is Walt's journey and what he said in the Grey Matter episode said it all.
For what time I have left, I want to live in my own house, I want to sleep in my own bed. I don't want to choke down 40 or 50 pills every single day, and lose my hair, lie around, too tired to get up, and so nauseated that I can't even move my head. You cleaning up after me. Me... me some um... some dead man, some artificially alive, just marking time... No. And that's how you would remember me. That's the worst part. So... that is my thought process, Skyler... I'm sorry, it's just I choose not to do it.