Oh, love. :( Those what if's will tear you apart if you let them. You absolutely, categorically did not fail him, and I honestly don't believe that there was anything you could have done differently - it sounded like it was a very sudden passing, and there's no way to predict those. You gave him a wonderful life. I miss him too, even though I never met him - I loved your updates and your photos, and how he clearly meant the world to you.

Big hugs.