Let's say she (or he - if it was a guy player), was into the RP during the romance, but after the culmination of the wedding, they then felt like the interesting part of the story was over. After that, the striving for the marriage goal had been achieved. Lots of times, courtships are more exciting in real life than the day to day maintenance of a marriage. In real life, the maffiage is real. But here, it's a RP game where everyone's trying to escape into situations that excite and interest them.
I suspect that K started feeling this way - constrained or whatever, knew that E wanted to keep going with the marriage, and was trying not to hurt his feelings by saying that RL interfered. Being up front would have been better, but not everyone who lives much of their lives in a fantasy world as we do is good at confronting uncomfortable situations if they can escape from them instead.
If this theory is true - maybe K really did care about E in that way, if not in such a way as to want to continue RPing the couple.
I think you guys need to have a truly honest OOC discussion to get past the hard feelings. K owes you an OOC apology for not being up front. As for RP - I think the wedding was a big event, much talked about - the whole RP up to that point obviously was successful. If things have ended here - well, at least you can still say it was a success to that point.
(And, besides, she could be a fat bearded guy anyway.)