Comments by "Limrasson" (@Limrasson) on "The Death of Merlin...and Why the Wizard Didn't Stop It! - European Arthurian - Extra Mythology" video.

For me this sounds like the true objective was to teach Nymue magic. It's like he wasn't in love with the woman he met, but he was in love with the woman she would become. Meaning that his love can only have an actual object if he goes along with everything he had seen. Also let's not forget that he is still a super wizard/druid and can probably chill in that cave for a very long time without issues.
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