27F, Breakup realisation after 3 years

Guys, idk what this is 😭 I’m not even PMSing or anything, but I’ve been missing my ex pretty intensely for the last 2 months. We finally talked properly on chat and I genuinely expected to feel that same longing again, but instead something just… clicked? Like I suddenly realised I don’t miss him? I still care about him and I obviously have years of memories with him, so I’m confused why I suddenly feel so detached. It feels almost foreign because I’ve been mourning this person so hard for so long. Has anyone experienced this kind of sudden “click” where the person you couldn't stop missing suddenly just… doesn't feel like someone you need anymore?