>Honestly I don't get how you can perceive that he's happier, but still see him as having changed "for the worse".
Well, from his perspective it's a worse change in personality, but from his friend's perspective he could be happier. So he's recognizing that his friend seems happier despite the change in personality he perceives to be bad.
Well, from his perspective it's a worse change in personality, but from his friend's perspective he could be happier. So he's recognizing that his friend seems happier despite the change in personality he perceives to be bad.