I'm going to purposely not invite my one aunt and her husband to my wedding
Why don't you want to invite your aunt and her husband to your wedding?
They are the family members who made my childhood a living hell.
This must be so hard for you. It's important to cut toxic people out of your life, and you are entitled to invite or not invite anyone you want to your wedding. Just be sure that the rest of the family doesn't judge you harshly for your decision since they may not know the reasoning behind it.
I'm going to spend the day in hell, but better there then with them.
Your wedding is your special day! I hope your family is understanding of your decision.