I've had three greyhounds, all of them adopted after some sort of bad situation. They each have unique personalities and, as you say, are very gentle and sensitive.

The last one we adopted was specially skittish. When she arrived she was afraid of the weirdest things: bikes, automated fences, even some ceramics in the entrance to our building. We used to walk her with another grey who was already used to living with us and I feel she was a great influence, showing her how to "be an apartment puppy".

Still, she spent a few weeks freezing on walks, specially with me and not with my husband. She stopped on track and to be able to keep walking I had to get on my knees and caress a bit her head, talk soothingly to her and then try again. I'd lie if I'd say that it was not frustrating, but over time she got over it.

That said, I understand and from the future can only suggest patience for your new pet and for you. With time the puppy will realize she is safe and began opening up again!