You just keep doing you, and don't worry about those who are unwatching. I deal with the same thing, except on tumblr. I've learned that it really doesn't matter who stays and who goes. My advice would be to not worry about who is unwatching you. If people want to unwatch, they will. If they want to stay as your watcher they will. I'm not trying to lecture you, but I guess I'm just trying to give advice. I don't know. Feel free to ignore me.