You have my sympathy. I'd cut out the night feeds one by one, to let him move his consumption to another time in the day, and then maybe reduce daytime feeds, if you want to.
My DS2 is 15 months, and would feed continually if he could. At around a year, he realised I always have my boobs with me, and started demanding milk a lot. After some wavering, I've decided to only feed him in my room or his room. (Ok, when we're staying elsewhere, the rules change, but it's still always a bedroom.)
He's learned that this is the deal, and will direct me to my room, when he wants a feed, which is annoying, but a lot less annoying than having my top yanked up!
I don't mind the current plan, which is about 4 feeds a day (morning, pre-nap, post-nap, bedtime). I have no idea how I'll cut down further, he loves boob so much, which reduces my motivation significantly.