I've been on the receiving end of this before, unfortunately. Both my partner and I had dates and his canceled. I asked if he minded if I still went or if he was feeling down (as being canceled on can do) and wanted me to stay with him that night.
"Oh no, I'm fine, go ahead and have a great time" he said with a smile.
I didn't realize until the next day when I got an angry, depressed text message from him that this wasn't his true feeling.
"Why didn't you tell me what you wanted/needed?" I asked, shocked and concerned.
"You should've KNOWN that it wasn't okay for you to go on your date if I couldn't go on my date."
I'm not a mind reader and I never will be. Even after 5 years, I can still be tricked by a happy tone and a smile, so when I ask what you need I expect honesty...even if its not what you think I want to hear. That's what I told him and I stand by it. My feeling is that he has no right to be upset at my failure to meet his needs if he fails to make them known to me.