I gave this answer in your last, similar thread
Now I also remember that we played Portal 2 together and that game was another perfect co-
op experience!
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Anyway, me and my ex-gf, now-wife have played a lot of games on PS3 and 4 together, so I have plenty of advice!
When it comes to actual co-
op there's this absolute revelation of a game, which is Divinity. We played Divinity 2 split-screen and (having been both tabletop and video game player for almost 40 years) I found it an amazingly refreshing experience. I really didn't expect that a complex
RPG with choices, dialogues and turn-based combat can work as a split-screen co-
op and yet it does and is absolutely amazing!!! Playing together feels like a real
RPG session when we can do things as a team or go our separate ways and explore the world.
If I was to recommend just a single game for couples' co-
op it would be Divinity 2.
In addition I recommend those two-player titles, all of them finished, all of them enjoyed by both of us:
A Way Out
Sky Force
Lara Croft and the Temple of Osiris/Guardian of Light
Towerfall Ascension
Shovel Knight
Overcooked 1-2
Also we very often play single player games together, and I think cinematic games with gripping narrative are best for that, as they are great for watching, not just playing. We loved
Uncharted 2-3-4 (1 as well but it's visibly weaker)
The Last of Us 1-2 (are in the process of playing Part 2, 17 hours into the game and loving it!)
God of War (actually started on PS3 with 1 and 2, played all of them and enjoyed all of them. I'd say 2 is our favourite)
Horizon Zero Dawn - not a great fan, but have to admit, a solid game and my wife loved it
New Tomb Raider games, wife has been a fan since childhood and 1st part.
Until Dawn was also a fun experience to share.
And then there's Witcher 3, which I played 5 years ago alone and now we are close to finishing the GOTY edition (finished the main plot and first DLC, stopped to play TLOU2, will go back after that) We spent ~150 hours with the game so far and never got bored. Note, though, that we have the literary background of the story, having read the books (me ~25 years ago as a teen

) which helps.
And the final option that is always there and will never go out of fashion - hot-sitting Heroes of Might nad Magic 3
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