He played hockey the last two nights, wants to go watch hockey tomorrow, and then plays two more nights of hockey,
BIG RED FLAG...
This is where I would investigate deeper. 5 nights of hockey in a row??? Are you really buying into that?
You have mentioned that you don't think there is anything going on with the woman at work. I don't think that concludes that he isn't having an affair with someone else.
I would encourage you to find out what is going on with this "hockey" obsession. What kind of evidence do you have that he is actually playing when he says he is? This has signs all over it that something else is going on other than hockey. He knows you will buy the excuse.