Ignore his temper tantrum. They all say that there isn't an affair going on and that they are "just friends". Notice how his defenses were already up and in place when it arrived home...he knew that you were going to have that discussion w/him and he wanted to knock you off base, which he did.
Oh, yeah, you must tipped the apple cart and made him decide the marriage was too far gone. Hello??? In his mind, it's been gone for quite some time and he's using the confrontation as the justification/excuse to say the things he is and for moving out. Let him go. He needs to grow up and face the big old world and see it's not all that it's cracked up to be on the other side of the fence.
Now, it's time to get up, dust yourself off and continue moving forward. You will need to watch your finances and keep the focus on you.
