Board Thread:General Discussion/@comment-4504826-20160426040035/@comment-27907368-20160527035231

I mean, Flowey doesn't actually love  - he doesn't feel those emotions anymore. He "loves" himself, and he sees himself in the protagonist and thus believes it was the person that he was closest with in death; the human SOUL inside of his own, .

Maybe Tsunderplane explains it best in the epilogue:
 * Admittedly, I may have had limerent feelings for you before.
 * However, upon examining my own actions, I now realize...
 * I did not love YOU.
 * I was merely infatuated with the CONCEPT of love.
 * The idea of romance, the concept of sharing affection with another...
 * Through these desires, I built a false concept of you in my head.
 * Such a relationship would not have ended well.
 * In closing, I believe it is better that I chose to say nothing.
 * Y... y-you i-idiot.
 * I'm not saying it again.