Shinebright, you are at a very courageous place, and have a made a decision that is very healthy and important for you. Congratulations!
For me, when I left my AH, even though I knew his abusive alcoholism and other addictions were causing me great damage, I still had a huge amount of loyalty to him, which persisted even when I knew he was bad for me. That was the next challenge - to free myself emotionally. And that takes time and a protective cocoon while you're doing it. You will get there!
Right now, you've done the most difficult thing of all: you've extracted your life from his grip and chosen to go on your own path and heal.
It is very early days, and you need to protect yourself in any and every way that feels important. I can fully understand not wanting to talk about where he is, and that seems very wise not to get caught in extended conversations at a social event.
Hanna, Zoso, Ann, they have some great suggestions about how to handle going to the wedding reception. I love the sample answers here.
I'd second the idea of telling someone you are really close to. You need and deserve all the support in the world, and you get to choose when you want to engage that support. Do you have a dear friend or relative who will be going to the event who you can talk to before hand and will act as your "wingman" to deflect people who ask? And, you can duck out of the reception whenever you want. You might take your own car so you are free to leave when you want to.
Remember, you never have to answer a question just because someone asked it!
Now is a good time to start lining up support for yourself - dear friends who can stand with you and comfort you, Alanon, counseling, whatever appeals to you. Your loyalty now belongs to YOU, and you only.
You don't have to live in a world of silence because his behavior is so bad that you can't admit what it is like to live with him. I was there, and it is freeing to be done with that burden of protecting someone else from the consequences of their bad behavior. I was very surprised, when I did choose to talk to people, at how much more aware they had been of his behavior than I thought. But the timing to engage or not engage others in what is going on in your life belongs to you.
Take care, come here often, I found a world of supportive souls and that made a world of difference to me.
ShootingStar1