Talk to the author of the other story and explain to him/ her that you did not copy their work. Maybe they will understand if you calmly explain it to them.
I read the author's story. I mean are stories are kind of alike. But in mine the main characters meet at a party, my character is the Devil himself, he wipes the memory of another person, and he doesn't have sex with the person he's making a deal with to make the deal(I hope that made sense) Also, in her stories, there are multiple people who her main character has made a deal with. In mine it's only focused on one. The stories aren't too much alike. I apparently used one of her lines, too. I don't know which one, though. -.- I just found out the story last night and I'm not sure what to do.
Don't delete your story. I think some people are trying to start stuff. If you ask the author for their story (You know to compare notes or whatever) and point out where the similarities end and where the differences begin, you can prove that you didn't plagiarize a story. I actually was in this kind of position a long time ago though sadly the author persisted that I had copied their story, their ideas, everything when in actuality, I didn't even know their story even existed prior to them mentioning it. So, see what the other person's story is like and see how exactly they're the same.