I haven't played GAMMA, but I played a ton of S.T.A.L.K.E.R. Anomaly, so I know about that game.
And there is a multiplayer mod for Anomlay, called Anomaly Together, but it's very much in beta, with a lot of issues.
If you wanna play Stalcraft in PVE, sure, S.T.A.L.K.E.R. Anomaly is an awesome game.
But no, if you wanna play S.T.A.L.K.E.R. with your friends, there aren't that many options.
Hopefully in the future Anomaly Together will be much more playable, but now, it isn't.

Dude, I saw your Stalcraft X review, and about how you wish the game was PVE.

I just wanted to inform you of STALKER G.A.M.M.A, it's a lot more demanding of your PC, but it's also free, entirely PVE and far more in-depth than Stalcraft. It does not, however have any multiplayer whatsoever.

Gamma is a mod for Stalker anomaly, which is in turn a mod itself, technically, but it's a standalone repack(both are, kinda), meaning it's also free, and while less in depth than gamma(also less demanding), it has a mod that allows for co-op with a friend, though I've not tested that mod, and it's also entirely PVE.

Either way, if what you want is a PVE experience similar to Stalcraft, you have plenty of options.

Bro, saw your review on stalcraft it is your honest review.
If seen how foul the children are reacting to it in the comment section just block them and set your comments off.

Do not add any of them or any request to speak to you 50/50 chance they go bully/Troll you.
They can't handle your opinion about the game, than they should not deserve to speak to you!