[WeLP. There's a loaded question.

Madoka is actively focusing her thoughts. It's not up to her to decide if the magical girls whose witches she defeats had happy endings. The decision for Sayaka, for Mami, for Kyoko, and Homura... None of those are hers to judge either.

And as for her wish...]

I think... Happy endings are more like... The kind of ending you can be proud to have lived for... Or something like that? Eheh. It's hard to think about in general terms.