I see some are taking as 'Still Ill' is mentioned it is a direct reference to Johnny as they wrote the song when they were in The Smiths.
However the way I take is that in 'Still Ill' Morrissey was clearly writing about someone from his past. 'Under the iron bridge we kissed.' Now to the best of my knowledge he and Johnny never kissed under any bridge (except possibly in Morrissey's imagination, haha) so to me I take the reference of 'still ill' in 'forgive someone' to be a direct nod to the same protagonist who was the subject of the original song.
'Still Ill' was definitely about a time pre-Smiths and this song also feels very much the same, reinforced by the 'sitting in the bleachers' line. I suspect the subject matter of both songs is the same person.
But hey that is just my take and as has been mentioned that is half the fun of dissecting the lyrics, the debate that comes with it.