How to cope with the loneliness after a breakup?

I (f25) recently ended my 7yr relationship after numerous attempts at trying to repair it. Things ended amicably, and we're still good friends with each other, but I'm having such a hard time just...being alone. As bad as it sounds, it's not that I don't miss my ex (m25), but I mostly miss the intimacy and the partnership of being in a romantic relationship.

Yes, I've been reconnecting and strengthening my friendships—which has been great—but it's not the same. With my ex, we were able to nerd out with no limitations about our respective interests, and definitely with our shared interests. I miss having that one confidant whom I can go to for anything and everything (be it a big or small issue) without the fear of being judged. I miss being all giddy with the cute, bubbly parts of being in a relationship: the cuddles, the dates, etc. I miss having that person to come home to after a long day.

It's not that I miss doing these things exclusively with my ex, could be anyone I've grown so attached and connected to. To put it bluntly: I miss being in a couple. Like, I see and talk to my best friend frequently, but even that strong of a relationship isn't the same.

It's been really hard adjusting and getting used to the new routine, but yeah, I know time will fix that. And, as childish as it is, I've become jealous of all my friends in relationships now. Like, I had that, but now it's all gone. I've been getting back to my reading and writing, watching new shows, going out with my dogs and friends...but it's still so lonely. It's like I'm waiting for the part of me that's missing—which, yes, I am my own being and I shouldn't need anyone to feel complete...but I so want that. I'm a hopeless romantic. I love love.

Anyways, that loneliness thing. How do I get comfortable just being by myself? How long does this feeling stay, or does it ever go away?