Well, Dan (and not only him) wasn't very happy with Fellowes writing and refusal to allow actors to aprticipate in the process, so... It was expected, to a certain extend. I blame Fellowes mostly, not only because of the lazy writing (and some of it is truly very lazy) but also for the authoritative approach. Now, as I rewatched seasons 1-3 I couldn't help but notice moments of complete writing failure. He also can't write happiness or sadness for the life of him and tries to avoid it, leaving much off stage. Anyways, to me Matthew and Mary were a very important plot device, aside from the purely romantic appeal, and I am quite happy now, revisiting their first moments, seeing them longing and staying away... It's nice.
But it's over, at the same time.