And this site translate "her" as his wonderwall (protetora), makes sense, because she "will be the one that will save him".
By the way, it fits the rhyming, since "after all" rhymes with "wonderwall", could be then a rhyming device used by the songwriter.http://en.wikipedia.org/wiki/Wonderwall_(song
According to Gallagher, "Wonderwall" describes "an imaginary friend who's gonna come and save you from yourself".
Or then, it´s not so imaginary as it was cracked to be...
"Wonderwall" was written for Gallagher's then-girlfriend, Meg Mathews, as Gallagher told NME in 1996: "It's about my girlfriend, Meg Matthews." However, after Gallagher divorced Matthews in 2001, he said the song was not about Matthews: "[the song was] about an imaginary friend who's gonna come and save you from yourself."