I installed it and launched it the first day I bought it but never played it. I just wanted to see if it would launch and noticed the creation club was gone etc. Which was fine.

Now today I wanted to start a new game so I hit play in GOG Galaxy the launcher came up then I hit Play on the launcher. Then that launcher disappeared... the Play button in GOG Galaxy turned green then the FO4 launcher popped up again even though the GOG Galaxy Play button was still green.. I hit Play on the game launcher the game launched but to my surprise it was the Steam version!

So I'm in GOG Galaxy wanting to play the GOG version but it's now launching Steam.

This makes zero sense to me as far as the installations go. Let me explain what I mean by that. When I own games on Steam and GOG sure the DRM Free is an advantage but another thing I really like is how I can have 2 SEPARATE installations isolated from each other.

I had to download the full installation for the GOG version but it's so intermingled with the Steam version it's making me question wtf is the point of even having the GOG version?! But now I can't even launch the GOG version because for some bizarre reason it's pulling from Steam now.

As mentioned in other threads for Fallout 4 here on GOG, there are issues when you have both the GOG and Steam versions installed at the same time. One of which being that the Fallout 4 launcher will try to launch the Steam version.

You might be able to get around this issue by changing the executable that runs from GOG Galaxy so that it runs the Fallout 4 executable (Fallout4.exe) rather than the Fallout 4 Launcher executable (Fallout4Launcher.exe), though I'm not sure how you do this as it isn't something I've had to do myself yet. It might be a case of editing some goginfo file, or adding/editing a shortcut within GOG Galaxy. Or of course you could just run Fallout4.exe directly.

This said, if you are planning on using any mods then you probably need the Fallout 4 Script Extender, so would use that to launch the game anyway.

Go to your GoG install directory, open the fallout 4 folder, right click on fallout4.exe, choose create shortcut. put the shortcut whereever you want, and use THAT to launch the game (bonus: galaxy doesn't need to be running)

Just a question . . . did you have the Steam integration turned on? If so, you might notice that when you hover over Fallout 4 in the launcher, it has a (2), which indicates you have 2 versions in your library. And the Steam version would be the version it would already try to launch. You should be able to change the default launch, but I'm not using integration so the only multiple versions I have is when I have a demo and the full game in the GOG library.