I have a couple of friends who have been in Ashley's boat and they have given their child (both boys) their last name. In each case they came from a family with 3 girls so no one was going to carry on their dad's bloodline, so they chose their last name. And they - who have no relationship with the dad of the child either- stand behind their decision and have no regrets.
One of my friends is the only adopted daughter of her parents - they had 2 biological daughters after they adopted her when they were told they couldn't get pregnant I think that is the best gift of all to give her child HER last name in a case like that.
That said I understand that Ashley's situation is different b/c she has brothers.