How do you let go of someone who was your everything?

I don’t even know where to start. We were together for 7 years — lived together, shared a dog, built a life. She wasn’t just my partner, she was the person I told everything to, the one who knew me better than I knew myself. When we broke up, it wasn’t dramatic or explosive. It just… faded. And that makes it worse? Like I keep waiting to wake up & realize it’s not real. I miss her in the small ways — the way she’d hum in the kitchen, how she always stole the blanket. I catch myself texting her dumb memes then remember she doesn’t want to talk. I deleted the photos — tried to, at least — but I still see them in my head. I’ve dated a little since, but it feels wrong. Not because I’m not over her — I don’t know if I am — but because no one else just… fits. It’s like my body remembers her touch & won’t accept anything else. Ngl, I didn’t think I’d still feel like this after a year. How do you relearn how to be alone when being with someone was all you knew? How do you make space for new desire when your heart’s still full of them?