Oh, just saw this. You might have found one already but going to suggest a couple anyway.
Riders of Icarus: This is quite an old game but it was a pretty unique experience for me so I'd still rate it quite highly to be honest. Plus I think was updated recently, big time, so it might have been revamped and closed the gap with more recent games. This is a pretty laid back game in general, the quests can be kind of repetitive but each map doesn't have a huge amount of them. Each map has a unique theme so the scenery can be quite nice, which IS relevant cause a big feature of the game is to tame monsters, which you can ride, so you could glide through the sky on your dragon, ride your huge scorpion on the desert or wander in space on your magically flying adorable squirrel. Plus multiplayer is heavily recommend it so if you're going to play with your bf, it just works out. And there's challenging content for when you're feel like getting a bit more serious.
Aura Kingdom: Pretty entertaining anime style MMORPG. It has a pretty cool "pet" system, except they're called eidolon in the game. There are also plenty of costume items so you could have fun with those. Many rewards are based on a lucky wheel-like system so you may get what you want or you may not. And if you don't, you may have to resort to farming, etc. I think it's pretty cool personally and my description doesn't do it justice, i's worth checking out.
Black Desert: This is not a free game, plus I haven't played it much. Sooo, I can't really say much about it or even recommend it but it looks cool I guess.
Guild Wars 2: Wouldn't recommend it for casual gaming. Not that you can't play it casually but I wouldn't say it's suited to casual players. As I see it, the game is like...99% endgame. I've seen people reach max level in a day, literally.and getting equipment one step before the best can be done in an extra day, if even that. After that, it's just endgame content after endgame content. Personally, I think it's pretty cool cause they tried to make the scale of the game that big and focus on "guilds" rather than individual players (hence the name of the game I guess), but like I said, not what I'd recommend for playing casually.
If any picked your interest and either you or your bf want more info on any of these, let me know Jackson.