I've been doing a lot of Duolinguo and it works like wonders to start picking a new language but then, at some point, it becomes repetitive and boring.
I don't have that problem. I guess your Duolingo work ethic surpasses mine.
However, if I'd become too bored to do Duolingo, I'd progress on something a bit harder like reading gossip magazines (they use simple language and have emotionally charged content, which makes it an easy read).
How do you deal with it?