First of all I am so sorry you find yourself here. So many of us know your pain and we are here for you.
Just so you know, my WH got my DS and the OW's kids together. For play dates at the pool and at her parents' house, etc. He told me about his "friend," but I just assumed it was a dude (I never had reason to not trust him).
Anyway, I know that it seems like you will always feel this way, but I am here to tell you that there really is a light at the end of the tunnel. You will get stronger. You will get through this. I can't tell you what your future holds for you and your WH...heck, I don't even know what my future holds, but take this time to do some thinking about YOU.
I know it is difficult to do this at times because it's hard to separate yourself as your own person from who you were with him, I found myself worrying about him and his feelings (which happens to a lot of BSs). Don't beat yourself up for the way you feel. You did nothing wrong and you are in shock.
Take care of yourself. Do you have family or friends you can confide in? I know many of us here would suggest you get some counseling for yourself. This is a difficult thing to deal with and you need the support.
Keep posting. I'm sending you strength as you make your way through this journey. We are here for you.