Bribing her with treats (as you call it) is a good start. Rather, let's call it rewarding her for passing through the doorway.
I think one of the best things you could do is to desensitize her to that situation. Just practice with the scenario on the doorway everyday for 5 minutes. It will take some time but rest assured that she such behavior will lessen as long as you do it consistently. Also, make sure to walk her. This increases your bond with Holly.
Before having a person stand there (to commence the desensitizing activity), make sure to do this activity without a person standing there. This is to give her a good feeling wherein she eventually understands that passing through the doorway is a good experience.
Later (probably after a week with everyday training), have a person stand there while you call her name to come to you. Once she passes through the doorway, reward her with a treat and give her lots of cuddles and hugs. You can also intensify the reward by playing with her using her favorite toy. Do this everyday until she no longer hesitates to pass through.
