Castle Crashers (PSN)
Try not to do too many games where you two share a character, or where powering up the character is an option to be specific. I encountered this issue with Brutal Legend. See, I love to collect power-ups and make my character strong. That’s fun for me in a game. Sandra, on the other hand, likes to explore. So much so, she ignores those power ups, even when they are out in the open. This led to a few arguments, as I thought she should be collecting the power-ups as she saw them. We fought so much, I actually got rid of the game. So while you share a character in Portal 2, you can’t power up the character anymore. Hence why I recommended it. Bottom line: Try to pick games were you each have a character.
Castle Crashers is one of those games to a surprising degree. Your character can be a physical powerhouse, a powerful magician, a speedy archer, or even powerful defender. Plus it’s a lot of fun, and a great one for online play.
Borderlands (PS3)

I can’t recommend this one enough, as this is one of Sandra’s and my favorite games to play together. So much so that its one of the few games we have two copies of. This game has everything I was talking about as far as a fun couple’s game. The story is so over top, and the characters and enemies are hysterical. It gives plenty of freedom to customize your character the way you want, and has several million guns to choose from. Even better? There’s lots of DLC to get to continue the adventure afterwards.
One final tip, and this is a good one with any relationship, talk to them. There is after all a chance that the games I mentioned today may not appeal to your partner. Find out what they likes, not just in games, but also in general. If they like watching Law & Order, maybe Heavy Rain would be more their thing. If they like being scared; maybe Dead Space would give them a thrill. If they’re big into music, get Guitar Hero. To get them into games, you need to find a lure, or something to get their attention. Getting a game that has something they’re interested in is a very good way of letting her see the diversity of games, and getting them into it.
So keep these facts in mind, and before you know it, you’ll have another gamer in your life. Somebody you can share new memories and experiences.