We just met, so I don’t know him that well, but he was honest from the beginning. He says he’s still married because of their son, and because his wife doesn’t want to get divorced right now. Apparently, South Korea has a fault-based divorce system. TIL.
It’s also a lot of legal rights and privileges. And in many places it’s also a default inheritance. If something were to happen to her, you would have no rights to make any decisions. Her husband would. Her assets would become his.
Even if you aren’t interested in being married, it’s in her best interest to actually finalize the divorce to avoid a litany of issues.