Why does everyone obsess over their exs?

I literally can’t take it anymore. Listen, I can understand that yes, you date someone and they have a big impact on your life, obviously, but honestly people need to learn to move on…. Especially in the lesbian scene. I am friends with this wonderful girl and we have both disclosed that we like eachother. However I ALWAYS find her saying some shit about her ex. It just feels so degrading. Especially as it has been years since then and you are trying to involve yourself with other people. I hate it. Always feel like some type of side chic. Don’t tell people you like them and then go on and on and on about your ex!!!! PLEASE!!! It’s honestly so disrespectful. Fuck all of you that bring it up or keep posting on social media about it when you are talking to other people. You all suck.