I'd been quietly and gently working with a "dumped" dog for about 6 months. He was terrified to have anyone within 10 feet of him. I'd go outside every day after work and bring him his supper and just sit and talk with him, scooting a little closer every couple of days. Nearly broke my heart when I gave him one of those Purina bones for big dogs (he was a big dog), and he immediately ran to the side of the house and buried it.
When he finally trusted me enough to come in the house with me, I was able to get him to the vet's and checked out. Horrible case of mange, heartworms, and about 100 pounds underweight. We started in on meds and as he began to feel better, his stress level decreased noticeably. One night I had him and my other dog (a border collie) in the kitchen and I took out "treats" for them. I told the BC to "sit" and he sat immediately and got his treat. I then turned to Porter, the rescue, and told him to "sit." His tail tucked under his butt immediately, the ears laid flat, and the most horrible, scared look came from his eyes. Instead of expecting a treat, I could tell he expected to be hit. I don't know who'd had him or where he'd come from, but you just knew he'd been badly abused. It also took him about 2x as long to get comfortable with my husband as with me.
We were able to spend quite a few years together before he died on Xmas day a few years ago. Whoever threw him away had no idea what type of dog they had. Turned out he was a Leonburgher, and he taught himself how to be a "helper" dog to me... helping me to get up from the floor, to bring me whatever I would need, etc. And he was so gentle, every one of cats adored him. I loved Einstein, our BC, of course but Porter and I had a special connection between us. When I took him to the vet the first time, he weight a little over 45 pounds. Totally skin and bones. When he died, he weight 125, and knew he was loved. Whatever he'd gone through probably shortened his lifespan before he found his way to us. But at least he finally knew what it felt like to wanted and to be loved. It just takes a long time with some dogs... especially the ones who'd been as abused for as long as Porter. I just bless the hand that guided him to our yard. And I still miss him, to this day.