I thought to myself what the f... how can someone think it's OK to continue to live like this and after telling me we are over he is building some sort of future. I do not understand.
Agree with In it - it's denial pure and simple. Pretend it hasn't happened and it will go away.
Detaching is hard with a stay at home MLCer because you feel as though you can't detach.
Your feelings of wanting to laugh and enjoy life will return. Many of us on here have noted that for months if not years some of us couldn't want watch romance movies - every TV programme that had a couple arguing or the script was about divorcing - we all became armchair analysts, we hated to listen to certain music and we all wondered when we would laugh heartily again.
YOU WILL! You will be able to be true to you at some stage. You will be able to laugh again and to watch programmes with a hmm or meh attitude. Have faith - this is a long process not just for the MLC crisis but the LBS inner turmoil that exists.
Look at the thread which is the stages of the LBS - that may also help.
Finally instead of using the word detach use the words "step back". Step back is a physical action and if you practise it every time your MLC says something illogical or hurtful or just plain silly - take a physical step back, lift your head, breathe and say " It's him not me.
Detaching is a process rather than a singular action. And the fact that you thought "WTF " is a good sign as long as you can see it as completely bonkers and an example of his crisis denial driven mind.
It's him and not you.