I actually don't try to quiet it - I give it a voice and tell T as much as I can. As soon as I say that kind of thing out loud, it becomes very clear how irrational it is. That helps me quiet it when I'm not with T.

And, like Hope-full said, it takes time. Time and trust in your T. The more I trust T, the more I can tell him and the more I tell him, the more I trust him.