<human>: Provide a brief overview of the text.

I've been with her for around 5 months. She is a wonderful, beautiful and super nice person and I can really see a future with her.

However, recently, she has started to call me by a nickname that a guy uses(d) for her. I know he calls her this because its all over her Facebook profile pictures, he has commented on her photos before we met calling her by this nickname along with comments on how attractive she is. This is all before we met, when she also commented on a photo of him saying that she misses him. He is the only person I know that calls her by this name.

I want a future with this girl but I feel so disrespected and hurt when she calls me this name, but also really confused because she's such a great girlfriend and I don't know what to make of it. I don't want to stay with her if she is hung up on this guy, no one in their right mind would. When she says it, i get distant and i dont know if i should bring it up or not. Although, I can't tell if its like she is trying to remember him or if she doesn't think of him at all and it means absolutely nothing. What should I do? I want this to stop. Am I being stupid?
<bot>: my gf calls me by a nickname that a past love interest used for her and it makes me annoyed. Should I tell her to stop? If I do, I will have to bring up what I've seen on Facebook