I do talk about things my fiance and I do together fairly often, because we do most things together, he has even to an extent taken up my musical hobby, and I've started going to his medieval stuff.
But to cancel plans with someone else in order to do something with him - that one I'd never do, unless it was some major emergency that I neede to help him take care of... it wouldn't be something I'd do on a whim just for fun. Since most of my friends tend to bring their spouses along when socializing, and we tend to share many of the same friends, most of the time this isn't an issue.
About the only time that I have made an exception to this was when we had a band rehearsal (for me, my friends are largely the people I play music with, so band rehearsal = socializing for me
) scheduled for Valentine's Day, half of the band was going to miss it anyway to spend time with their SOs, and he asked me out that night. And then our band leader's wife got wind of the fact the he was scheduling a rehearsal on Valentine's Day, and made him cancel it anyway to take her out. *LOL* She is great, she's going to be the MOH at my wedding.