The only way is to deactivate and find something else to do. Then you can come back twice a year for the Return to Vanadiel weeks to get your fix. It looks like the next one should be coming up late next week. I started a Yagrush last time, got everything done except the alex. Woot only 30,000 alex to go!
But yeah, the first thing to do is kill the auto-bill and go month-to-month on crysta. Before I quit (nearly 3 years ago?) I was buying 2 months of crysta at a time. I just had to stop.