I am not a Facebook fervent user. I use it because of some of my friends are using it.
So, if you want to enable your “available to chat” status to your group of close friends or special group of friends,
- Go to Friends an create a list that you want to chat with.
- After creating the list, add your close friends.
- Now, turn on the Chat.
- Go to Chat Options > Advanced Settings
- Choose “Turn off chat for all friends except…”, and add in your target chat.
Then, if you are using Pidgin, you can use chat with your Facebook friends by following this instruction.