Ex kennel dog

[Tresco]

We re-homed a 5yr old GSD in June last year, breeder was supposedly re-homing her because she was a little quiet and she felt that a pet home would be a better environment for her than retiring on their farm/kennels, advertised her on the internet and we picked her up.

She is now, and this has worsened in the past few months, very afraid of me in the house. She will bolt out of a room if I walk in, cower if she sees me and will not come if I call her in the house but just lays in one spot all day with her head turned away from me. she has though absolutely bonded with my Wife.

The strange thing is that out of the house when I walk her she is very affectionate, tail wagging, and playful yet as soon as I open the garage to go back in the house she cowers in the corner.

After some investigation into her history it turns out that she went from a previous home environment at 2 years of age into outdoor kennels with 20 plus GSD's, had four litters which produced 30 pups in total and was then, I'm guessing, rehomed once she'd served her purpose.

We've had a rescue GSD before so not dog novices and I've tried not having eye contact, always being at her level and talking in a very soft voice etc.

I'm wondering if the trauma at 2yrs old is the reason that she is the way she is? Perhaps a man at the kennel mistreated her and she sees our house as a kennel?

Has anybody any experience or advice they could share?

Thanks in advance.