Mourning and grief are very important, as rituals and rights of passage. If we don't do it consciously, then it is going on further down, and we know from our MLCers what failing to fully acknowledge our feelings can do!
Like Creed I did my crying before the divorce, and by the time the divorce came it was a relief, because of the abuse that went on during the process. But if you feel sad, acknowledge it. Keep an eye on how long you are grieving though - if it goes on too long it can become a way of life, if that doesn't sound harsh.
As to whether or not your marriage is over, that is in God's hands, and also your h's. He may wake up and realise he was a fool, or he may not. Taking BH's advice to the logical conclusion we should stop standing the minute they walk out the door, because they wouldn't have done so if they wanted to be with us. I believe totally that MLC exists, and that our spouses change into something else. I went on loving the person my h was, and hoped he would return. He didn't, and probably isn't going to. The way he was, he was still the person I most wanted to be with, and I have not met anyone else. Am I standing for my marriage though? Probably not. My new life absorbs me more and more, although at times i still miss him acutely. That is a sign of our depth of feeling. Some people find someone new, others don't. There are no rights and wrongs here, only compassion and understanding for the path each of us walks, with so many similarities and yet huge differences.
The 2 x 4s are meant helpfully, as are the words of sympathy and love. You know that from raising children. Sometimes we need sympathy, other times a good talking to!
We all feel for your pain, we have all felt pain, and we want it to stop for you, preferably NOW. Each of us has a different idea how best to deal with it.