Nelson was fired because her boss and his wife felt she was a threat to their marriage.
The Iowa Supreme Court ruled the dentist acted legally when he let her go.
"I don't think it's fair, I don't think it's right," Nelson said to CNN. "The last couple of days have just been an emotional rollercoaster. I'm trying to stay strong."
Nelson spoke one day after the all-male Iowa Supreme Court ruled on her case.
The high court sided with a lower court, ruling that Nelson's termination did not constitute sex discrimination under the Iowa Civil Rights Act.
