2 or more people I consistently get disconnected.
I was not the host but when I switched to being the host it disconnected.
Sometimes it’s as soon as 2 minutes sometimes half an hour.
I never have this problem playing alone.
I keep the graphics set to medium and low for some settings not sure if lowering the graphics creates more problems.
I use a msi leopard pro laptop with an Nvidia gtx960
Graphics shouldn’t cause any problems like that. Might be your internet connection 
I have ridiculously good internet.
try to host it yourself, had the same problem a year ago, when I hosted it was gone.
Maybe in the setting of one of you the UPNP is unsuccessful or the NAT type is set to moderate/strict.
This changes the ability to host games or join someone drastically. Looking at the properties of the router should tell you if it’s your network
I was trying to find a co-op last night. Kept getting the blah, blah timed out message. Went to my game and switch it from invite only to any can join. Got a message that I was no longer on steam. Could not open my game in multi-player to change my setting back. Then tried joining a co-op game again and was successful but could not find a game without players using mods.
Went back to my own game and changed my multi-player back to invite only. Started having players joining my game. When I tried to kick a player that was using mods nothing would happen. So I had to close my game completely.
Would really like to see these kind of problems solved before a lot of time spent on coming up with paid DLCs.
Even reading the daily comments, more and more players are posting ways to work around all the bugs and issues these NEW DLCs are causing.
I get the feeling that since landfall update, or after that, something is going on with the game and steam.
Before it was never any problems playing offline, now the game crashes immediately when entering combat when trying to play offline.
And now more and more people are reporting steam-related crashes