Mine were all draining setons as well. After having the various setons in for about 9 months in total they finally did the LIFT surgery. That is where they tie off the two ends of the tract going through the muscle to stop the fistula tract from continuously filling up and draining. My fistula tract went through the muscle which is why they had to do the LIFT. I've also heard of people have the plug procedure which is less invasive. I asked my doc about the plug and I was told that the LIFT has a better success rate, although technically it's still only 50%. When they did the LIFT they laid open the rest of the tract - I had a HUGE wound.. they actually kept me overnight which I wasn't expecting. Not to scare you or anything - it was huge but didn't hurt any more than my other surgeries. What's next for you will depend on where your fistula is located - I assume part of it goes through the muscle since they placed the seton? It will also depend on how you continue to drain and heal up. When is your next follow up?
I find that soaking in the tub isn't as effective as the sitz bath that fits over the toilet - can you get one from your drug store or maybe online? Also, are you using epsom salts or sea salt at all? I've used both and prefer sea salt as it has great healing properties.