The memories Severus gives to Harry IMO are less a testimony of undying love than a confession. Not one of them presents the Saint!Lily he is supposed to love; they show his mistakes

That's a great point! Really brilliant.I'd never seen this put quite that way before, and I think you are right.

But, again, I don't think Sev's repentance can be separated from his love. I do think he always loved Lily, and what I'm arguing against is the idea that this love and faithfulness are weakness.