Step father dance

There is no need to mention anything to anyone.

Sounds very complicated, but I can understand why your dad doesn't like your step-dad. I wouldn't like someone that my spouse cheated on me with either. I would probably sit down and have a one on one conversation with your dad about how you'd like to include a special dance with your step-dad, but given everything that happened with your mom, step-dad, and dad he might not take it well.

I think it would be considerate to tell your dad before hand - that way he has a chance to mentally adjust to the idea (even if he doesn’t like it) and you have the opportunity to explain why it’s important to you that you do it. Springing it on him without warning could cause all sorts of upset all round.

Absolutely talk to your dad ahead of time about this.

Give him space to have the hurt for his marriage, but also, very gently, remind him that you were a child in all this, and their complicated feelings about the adult relationships that were disrupted... are not your responsibility.

I'm sorry, my parents are divorced, too, and, until I cut contact, my mother loved to try and litigate the divorce with ME.

I don't know the specifics of your family situation between your Dad, Mom, and Step-Dad regarding why or how your mom left. If it was because of cheating, consider that sometimes when people cheat it is a symptom that something is wrong in a relationship (like feeling emotional neglect). I am not saying cheating is right, or that this is the only reason people cheat. I am only stating the reality of the matter. Either way, the ins and outs of your parent's relationship, and step parent's relationship with each other have nothing to do with you.

I would say to have a heart-to-heart with your Dad: You love him, you acknowledge his pain, and you want him to be there. Do mention (and you can keep this brief), that your Step Dad (refer to him by name) has treated you with kindness, and you want to have a dance with him after the father-daughter dance. You don't want to hide this or cause him more pain, and you also don't want drama at your wedding.

If your dad understands, realize that it is an emotional sacrifice for him, and acknowledge that too.

Do touch base with your step dad one on one. You understand that the situation is complicated, you appreciate his influence in your life, and you want a moment with him that is special. You just ask for him to understand that him having the dance "second" doesn't mean that he is second rate. You just don't want hard feelings or drama.

This is a very compassionate way of approaching the situation with all parties. Kudos!