There is always potential for drama. But there is always potential for no drama as well.
Really-this is his situation to manage-so how involved you CAN be is going to be up to him.
I wouldn't stress out too much at this point. It's new info for everyone. The best thing you can do as his girlfriend is be supportive of him with this new info. Ask him what you can do for him.
"Love As Thou Wilt"