What a nightmare for you. I agree with Linda, try a head collar and don't let her off the lead. I's a hard one to try and advise by the written word but there are some techniques you can try.
When you are approaching people, draw her head to you and gee her up - talk really happily to her perhaps have a tasty treat so that her attention is to you - not the approaching people.
You must be confident - if you are at all nervous, she will pick it up and that will feed her anxiety. It's hard, but essential. Walk quickly and confidently up to and straight past people, don't slow or let her slow. She'll be too busy trying to keep up with you to have time to bother with the people. She is likely to try at first, but in time should ignore them.
You might also want to try an anti-bark muzzle on her too. You need to be able to concentrate on her behaviour and if she's barking at people who may then be grumbling at you it will distract you.
Take her to places with lots of space and people. You can then keep her her at a distance from the people while you start this new regime. Gradually, over time, move her closer to the peole. Make sure you reward her when she is doing well and ignore the bad behaviour. A firm "no" is good, but then move on.
I also think you need to do this on a one to one basis. YOu can;t do it with another dog by your side. What is more likely to happen is the anxieties that Holly has will begin to rub of onto Chloe :-
hth