I use to feel the exact same when I started working as a freelancer. i'd see friends once in a while but unless I decided to go out, I wouldn't more than one actual conversation a week.
Then a friend introduced me to bouldering, which islike rope climbing, but on much smaller walls, without ropes, and huge mats on the floor. I've always like sports, so I was hooked, but after 2 years now, what makes me stay is the people I've met there. I can go and exercise, get out of there completely crushed and happy, but I'll also meet people, some stronger than me who'll happily give me advices, help me, some just starting to whom I'll give an advice here and there, and after that we all have a beer, talk about our common passion for climbing, discover we have more in common and nowadays, more than half of my friends are climbers, and it's really great, we plan weekends out climbing, watch the competitions together and always have a great time.
Another nice thing is that most climbing gyms have a restaurant, wifi, when I just have to be on my computer but don't have much work to do, I just go there, plug my computer, work for a few minutes, go climbing, come back to check my emails, nobody cares, I have a great time.
So yeah, if you like sports, don't want to just lift dumbells (which I tried to do but got too booring to me) then climbing might be something great to do for your body and a place to meet really nice people. I'd just avoid rope climbing as it often requires a partner (unless you don't care bout the rope but I doubt it) and the feedback loop isn't as short (completing a 30m routes is more difficult than a 5m boulder in just one session).
The co-working space is a nice idea, though it can be quite expensive, that why I didn't do it. Cooking lunch for friends working near where you live might offer you a real break and an easy opportunity for you to see your friends too. Plenty of things you can do actually !