Oh Max, my heart breaks for you. I, too, am at a loss with my marriage. I thought everything was fine until I was told it wasn't. Its such a shock, like being hit by a car. It stops me in my tracks some days, and I have to catch my breath.
Your pain is very very raw right now, and you aren't detached from W. When this happens (you'll feel it slowly start), it'll get better.
The lame cliche, what doesn't kills us makes us stronger, rings very true for our cases. It won't physically kill us, and we will go on. The sun will rise, blah blah blah. But its true, and it will be alright. It will get better.