I can really sympathise. We've had similar problems with Dylan (see two previous threads). First time paw to ground he was duffed up by a Jack Ruseell and thereafter screamed whenever any dog came near him. That would have been around nine or ten weeks old. Before that he was friendly and confident. First obedience class we took him to was rubbish, but we now go to a much better one. I took him for a walk with a friend with an old,black lab who just ambled along with him, and the classes have really helped. At first he was scared, but has gradually been coming out of his shell and gaining more confidence. We go for a walk once a week with a lady with a beagle puppy from the class, and although she is a bit of a bully, they have been off the lead together and he is beginning to,stand up for himself. We visited each other,s house and let them off together in the garden. Now he is keen to get into 'school', and he says hello to the bigger dogs quite happily. He still doesn't,t like bouncy dogs and looks apprehensive hen they rush over, but the screaming has stopped and he is much better. When he stays brave we praise him and treat him, and his confidence is really growing. Just have to be care ful we don't get a setback. I don't let hi off lead in the country park yet because he could disappear into the trees if scared, but we go to the beach regularly where you can see any dogs coming an get him on the lead before trouble occurs.
If you can find the right dogs to socialise Millie with hopefully she will also get more confident. The street walking is a good idea too.
Lesley and Dylan