I've asked this before regarding ps2 games, but other than persona 4 she had trouble playing most games with the controller. 360 games are even more of a struggle since the controller is a bit larger. I haven't touched my wii in over 6 months so I ended up giving it to her, other than wii sports/wii fit she has't played any other games on it. I'm not looking for games that we can play together, rather stuff she can throw in a play on her own. She's played several DS games and PSP games like Patapon. Again, it doesn't need to be a "real" game that GB users would want to play, she just wants something she can handle without becoming frustrated.
Wii games for the girlfriend (to play alone)?
Kirby's Epic Yarn is a fun platformer. It's not too difficult, but the level design is awesome and it has 2P co-op if you do decide to play MP. Super Mario Galaxy 1 and Super Mario Galaxy 2 are both great platformers as well and aren't too challenging. Little King's Story is a pretty easy-to-play RPG/SRPG as well, though it definitely can be frustrating at times so that might not be the best choice.
Other than what's been mentioned, I enjoyed Fire Emblem: Radiant Dawn, but that might get too hard, especially if she doesn't play it on the easiest difficulty setting. (unless the difficulty is just coming from not being able to use the controller fast enough, which wouldn't be a problem at all here. All about the mental challenge.)
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