With every new day you get to decide whether you want to clutter it with the past. I'm not suggesting you forget and sweep things under the carpet, but dragging resentment around leads nowhere.
Your H is starting to do the work of recognizing what he's done and starting to repair it. You are going to have to learn to trust him, little bits at a time. Send him off to the company outing. See if he comes back and tells you all about it, and puts your mind at ease. If so, you're one step forward.
On the other hand, if you prevent him from going, you stay stuck in fear, and he'll feel controlled. Not what you want.
Of course you wish the OW would disappear, but she isn't going to. Keep in mind that in the battle for your H, you won. She's road kill, let her go.
