To note, both the friend that started the server, and myself had restarted our PC's
I just started experiencing this in the last few days. I can connect to a friends server just fine, but trying to connect again, even after a computer restart, just ends up with the loading screen freezing. After many tries sometimes the game loads into the server, but almost every time, it either stays stuck or goes black screen. There's also a small chance it will load into the server but it will lock up the moment in-game visuals are seen.