Woogie, my birthmother gave me up right after I was born, and I was raised in a wonderful loving family. I was also aware of my adoptive status from the beginning and was never treated as if this was something "bad". I am 30 years old now and have regained contact with my birth family. The confidence that was instilled in me by my parents (adoptive)regarding my worth and love has enabled me to see that the reasons surrounding my adoption, while a difficult choice for my mother and others involved, was for the best and was a loving choice.
Your girlfriends issues don't completely stem from just her birthmother's surrender. There are other outlying issues she needs to address.

Adoption is a beautiful thing, be it straight, gay, single or married. Every child deserves a loving family.

Surrogacy isn't adoption. It is paying someone else to have a child for you. At no point do the genetics of the person the womb is attached to enter into the equation. A woman who enters into a surrogacy contract is aware of this, as is the father. If you were a product of artificial insemination, would you feel the same way about the sperm donor?