What does it mean when a girl talks about her ex boyfriend?

I've been spending time with this girl, and she keeps talking about her ex boyfriend. We have a lot of fun talking to each other, and she at least seems to really enjoy my company. Every once in a while she will throw in something about her ex boyfriend.

Example:

I talked about how I interned in Los Angeles during the summer, and her ex boyfriend, whom she broke up with two years ago, lived there.

I said that I own a house and rent rooms to people, and she talked about how her ex has a huge house in Los Angeles.

I talked about how I have my own company and I'm starting up in the music industry, and her ex boyfriend rents out his house for people to record movies or TV shows in. She said that a reality show was shot in it at one time.

She's here in Minnesota, so there's no chance of rekindling that relationship until she finishes college up here and if she would decide to move to Los Angeles again. She also broke up with him a couple years ago, and it seems like he was the last guy she dated, at least in length.

So, why would a woman bring up her ex boyfriend?
What does it mean when a girl talks about her ex boyfriend?
Post Opinion