How do i invite her without inviting him?

This is really personal, but I need advice. I never had a good relationship with my dad, he was manipulative and abusive and it's been six years since I've spoken to him. My stepdad is the most amazing guy in the world and he's been my "real" dad since he came into my life, and he's walking me down the aisle and everything. I have no interest in inviting my dad and I don't feel any pressure to. The problem is, I want to invite my stepmom. She is one of the most amazing women in the whole world. She loves my siblings and I like we're her own. She's told me before that she would have left my dad a long time ago, but she stays because of my siblings (who still have a relationship with him) because when she's around he's a lot better and he doesn't treat them the same way he treated me but he's still just not a nice guy at all. I talk to her on a semi-regular basis and even though I rarely see her I still love her the same and I know she loves me the same. I really want to invite her to my wedding, but I don't know how I can invite her without inviting him. And I worry that if I do invite her and not him that he'll be angry with her and it might cause issues between them. Or she might try to convince me to invite him which would be a really uncomfortable situation. I know the easiest thing would be not to worry about inviting her, but I want her to be there. Does anyone have any advice for what I should do here? And if I do invite her, any tips for how to do so while making it clear that he isn't invited? My worst nightmare would be inviting her and him showing up along with her.