Since I have moved into an apartment, my dog has lost its self-confidence. How can I help her re-gain self-confidence?

Hi, you have a FANTASTIC website! I suspect the answers to my questions are available on your website. However, I haven't been able to locate them yet, but if you could point me in the right direction I'd be very grateful. I have a 3 1/2yr old female GSD (DDR bloodlines). As a pup she was very self-confident, over the past 2 years I feel her self-confidence has gone. I know it's my fault... 2 years ago I had to sell my house, since then we have lived in a little apartment which is part of a 4-apartment house. So there's all the stress of living in a situation that is not suited to a dog... no barking in the building, there is no yard for her to go in - EVERY time she needs to go out to the bathroom, etc., we drive over to the Town Garage where there is a huge field. She is VERY friendly to people she knows when in familar surroundings, but if we go to someone's house that she doesn't know and I take her out of the truck to meet them, half the time she tucks her tail, trembles, and tries to slink back into my vehicle. She's not in least bit aggressive in these situations. My reaction was just to hold her and talk to her calmly and then let her get back in the vehicle within a minute or two. Seeing how it upsets her I try to avoid these situations, but realize that is not dealing with the issue. I know our living situation is a big problem, and I am trying to find somewhere more suitable, but also I strongly feel a key factor in my dog?s reaction is due to a TERRIBLE experience at the vet's office she had last summer... needless to say I will NEVER allow that vet to touch any dog of mine ever again! I want to help my dog re-gain her self-confidence, but am not sure how to.

My second question you'll probably wonder if I'm talking about the same dog... as a young adolescent she & I were attacked/chased by loose neighborhood dogs when we were out walking on several occasions. Result, my dog is very aggressive if she sees another dog when we are out walking. So I tried having her sit quietly to the side of the trail when a leashed dog would walk past... she was getting the hang of it and sitting very quietly, just watching the other dog. I was thrilled! Then a few days later, some idiot with a loose dog comes charging and barking at us ferociously. I feel like shooting these irresponsible people! (Of course my reaction just makes it worse!) All this work I was doing with my dog was in parks that stipulated dogs had to be on a leash - so much for enforcement. Since then I have resigned myself to avoiding, as best I can, situations were my dog & I will encounter other dogs. I feel this isn't fair to her, that again it is just avoiding the problem, there must be something I can do? Lastly, regarding prong collars, wouldn't using a small prong collar with extra prongs (links) be more effective on a dog then using a collar with bigger prongs therefore less actual number of prongs (links)? Looking forward to any insight or suggestions you can share.

Thank you so much for your time,
Sarah