BoxerLover,
I did stick my foot in my mouth. I am sooooo sorry! Your story was beautiful and if I could I'd put angel wings on your back. You certainly deserve them. Nikki is very blessed to have you in her life.

You can use the above method I described with teaching her to get over her fear of men. Just change big dogs for men. The theory is the same.

The story you told indicates that Nikki never had the chance to be properly socialized as a puppy. When other pups are still being socialized (the first year is critical) she was having babies of her own. She has missed out on an important part of her puppihood. My strongest suggestion would be to enroll her in a training class specifically designed to deal with such problems as barking and agression. Just having her around other dogs is a great socialization benefit to her at this point. The trainers will be able to pick up on any apparent skill that needs specific attention. Usually by the end of the course, most dogs can be fully integrated back into their local canine community. The best results are achieved by highly motivated owners who enjoy close bonds with their dogs. Sounds like you should succeed with flying colors

As far as Abby is concerned, I wouldn't push it. Maybe after Nikki's socialization class you can try to see how they react together.

Here's a thought: See if Abby's owners would enroll her in the same class that you join. You can learn together.

Best of Luck to you!