Welcome to your wife and sons!
The meet part is easy, really. We just all chat about past cruises or answer questions about anything and everything for those that haven't ever cruised. We'll eventually plan an actual meet for embarkation day. Nice to meet up so there are familiar faces at events. Kids have familiar faces in the kid's clubs.
Send her over to the Facebook group if she'd like.
The FE works like a secret santa. Sorta. The only rule is that you have fun with it. You make or buy a pocket thing to hang on the fish and make or buy little trinkets to give to the other people in the group.
How old are your kiddos? I'm also having to leave one of mine behind also, which makes me sad. My 4 year old twin boys will be on this cruise.