Well, when he gets home, don't even show you are suspicious of his activities, because he was probably not doing anything bad, anyway. Maybe he was just thinking of you, and not disturbing you by coming home late, and being drunk. He seemed upset at that w calling you that day, so I don't really think there is anything going on, anymore, if ever. Just act as though it were a normal day for you, and be cheerful and give him a smile and a hug, and ask how his night went. I am having to do that, too, when H sometimes works late, and I have no way of knowing if he is really still at work. Just don't show how upset you are, because you don't want him to start thinking of the old you.
