Camwen
In my opinion (and experience having had lead a guild for a while) The number one thing that keeps a guild active is simply this: BE AN ACTIVE MEMBER YOURSELF. Yep - the best way to keep an active guild is post - a lot. Don't wait for other members to post. Reply to everyone but don't only wait for people to reply to you.
Contests are great when you already have some active members to keep things fun but they don't actually make people who are not active much more active.
Don't post about where people have gone and how quiet it is. That just makes people feel bad - it doesn't actually help things. Just start a conversation yourself.
smile Be silly. Ask a question. Post a pic.
Also, you can drum up more members by going to the Gaia Guild Network forum. http://www.gaiaonline.com/forum/gaia-guilds-network/f.156/
Find someone else in the guild that can help you and have a conversation to keep your thread in the Guild Network bumped up. Conversations are much better than just saying "bump" and hoping someone bites.
All this!
And
Your story breaks my heart
crying In my opinion it's not a problem for a 19 year old to run a guild. After all, the users don't really 'have to listen' to the owner. Polite conversation doesn't really need a boss, right? And if it's too much to handle, don't feel bad. I'm sure you have more important things to worry about right now
emotion_hug