@Easycheesy,
To be honest love, this is a typical male reaction when the man is under pressure.
Now my advise is very simple. Don't police anything. Create a genuine carefree and fun environment for you and your hubby, and if you see he embraces this change you are good, if he still daydreaming and looking for excuses to be alone and away from you, make your decisions.
And by decisions I mean the only two choices
A. Live with it. Don't try to find anything, just live with it as it is.
B. Move on.
I hate when people want evidence for something which is so obvious as being emotionally apart from each other. You know why people seek evidence? Because they hope they're wrong. They are never wrong though.
So save yourself from the frustration you ll get into if you try to play it a detective and confront the reality of your relationship.