You can't blame them. They are desperate for servants. I've never been an MS. I tried for quite a while, but my time was never enough or my meeting attendance was never enough. They've recently stepped up efforts to encourage me to do more. Oh if they only knew...
Wish I had advice for your situation. Maybe if they take away your responsibilities and you're a MS in name only for a while you can revisit the stepping down again later. If you end up moving, it would be a moot point.