Ex's and feelings

Serious question. Do y'all think ex's actually stick around because they still have feelings for you or just because it didn't work out with anyone else? I'm currently dealing with this with my ex. I don't really have feelings for him anymore so it doesn't make me feel sad talking to him but he be mad flirting (I do not flirt back just an fyi). He dumped me in August. I don't have him blocked because we got a kid together because otherwise I would. I seriously feel like he still has a thing for me but maybe he just ain't getting the attention he wants from someone else. Relationship