What to do with a pregnant dog?

I bought my purebread dog from a friend who breeds them. I have been taking her over there the last few months for them to dog sit for me. This morning I went over to pick her up and she is pregnant. I have been on vacation for the last two weeks and coming back it's pretty obvious, she looks huge. I am furious because this means that my dog is pregnant by the male that is also her father! I cannot believe this happened. My friend says this was an accident, but she was supposed to be watching my dog and keeping her separate, that's the entire reason I trusted them instead of using a dog kennel while I am away. What am I supposed to do? Are these pups gonna be weird inbreeds? Should I just take her to the vet, is there even such a thing as dog abortions? I don't know if I have the heart, they still are living beings. What now about our friendship. I feel so frustrated at the same time I understand accidents happen. Please give me some suggestions. Thanks