It’s not terrible to want to have a relationship with her father. But the OP did three things wrong: She gave in to blackmail, as if a relationship with a parent who would blackmail her is worth anything she let her bio father use her as a weapon to inflict cruelty on her stepfather, as if a parent who would use her to carry out his revenge is someone worth having a relationship with, and she hurt the stepfather who genuinely loved her. The only solution is to get a divorce and then get remarried with the stepfather walking her down the aisle. OR, possibly, a letter to her stepfather not only explaining that she now understood what she did, sees her bio parent for who he is, and is cutting the bio father out of her life until he personally makes a full apology to the stepfather,
