unfortunately i'm not as good as you, and when people push me to do something i simply can't do, because it goes against my "inner guidance system" i just shut them out, and cut them off completely.
IMHO if someone is willing to totally disregard my boundaries then they can go to hell. sometimes if it's someone i care a great deal about i will try to reestablish the relationship (friends/family/etc.).
maybe someday i will be able to control this, but honestly it works for me, and i feel a weight lifted off my shoulders when i go through with it, as i don't take this action lightly, and only do this when i feel it's absolutely necessary.