Yeah, it is harder to be friends with your coworkers when you are remote. You do end up developing relationships though. My mom, for 30 years, spent so many years on the phone with other people, when they finally met up, it always ended up in friendship.

I work from home exclusively. I am in the same boat.

Earlier in my career, it was easy to make friends at work. I miss that. Lets go golf! Lets go drink! Lets go do this... etc.

I do think that ended up creating 'cliques' inside the groups though. Its probably better in the long run to try to establish a more professional relationship with coworkers. Just my opinion - and i'm likely wrong.