OP, right now you have the upper hand because you are the one who is going to have to file. So, while it's normal to feel emotional, stop. Get all your ducks in a row, documentation of everything, and find a great attorney. Do all this before you confront your DH and work on getting the best settlement possible.
My ex was at his AP's house until midnight the night before I gave birth to our son. I got through it, and so can you.