What would happen if your friend relationships had a lot more similarities to romantic relationships? Scheduled outings, regular discussions about what is pissing you off, regular apologies, mundane/unscheduled time together, discussions about hopes and dreams, declarations of affection. Probably less physical touch...

Anyway, I feel like people think they can let friendships develop by osmosis. I don't think ANY deeply fulfilling relationship can just happen without real relationship work.