War of the Rings plus expansions.
I finally got my boyfriend to the point where he can play complicated games. His only prior exposure to boardgames was stuff like monopoly. I had been gaming for years so it was really unfair matchups. It wasn't fun for either of us when he didn't understand what was going on and got frustrated. So I had to ease him into it.
We mainly played co-ops but I increased the complexity of the games I introduced to him. Last year, after 2 years of gaming, he played and enjoyed Arkham Horror second edition. That's when I knew he was ready for War of the Rings. We played it for the first time a few weeks ago and it went well. I'm looking forward to adding the expansions next time.