
I have never known of anyone having a c/section because pups are being absorbed, I think your friend needs to find a new vet.
Hormonally her pregnancy was stopped part way through with major surgery, so the normal hormone progression didn't happen, she then didn't have pups to raise so releasing the nice nurturing hormones and is probably totally confused as to what has happened to her and reacting by trying to protect herself.
It is early days and provided she is eating and drinking properly then just give her time, don't force her to do anything that causes distress like leaving the house for a walk. I presume her wound has healed up with no residual pain and there is no signs of infection,urinary or vaginal, check her temp to be sure.
If your friend is worried about this vet surgery then find a new one she can trust as you never know when you will need help in an emergency.
Keep us posted.