This is a well-done villanelle. I think it was an interesting choice to use the repetition to sort of follow them through the years and show that Bella (I assume this is Rodolphus to Bellatrix) has made the same choice over and over, turning from him to Voldemort. It's also an interesting characterization of Rodolphus - though I suppose one of them probably had to love the other, you don't often see that from some of the more loyal Death Eaters. And I don't see Rodolphus' jealousy of Bellatrix's love for Voldemort explored a lot. So well done. :) I think the "darkness sears your mind"/"piercing flame" line is my favorite - the contrast makes for an interesting image.
Author's Response: Thank you so much for the comprehensive review. I'm glad you thought that it was an interesting choice; it was what the prompt inspired!
Is it a man who loved a woman who became a follower of Voldemort?
Author's Response: Yes, this poem is about Bellatrix, from Rodolphus' point of view. Thanks for reading and reviewing!