Spoiler (highlight to view)
Only in the first Rou OAD do we learn that Himawari is married. As of ch.207 we have not gotten anything to substantiate that she is in the manga as well. It may or may not happen, because the OADs are being used to move the manga story faster. So the events that happen may or may not be repeated, but since the OADs are trying to help move the story faster there's no sense in repeating those events. As long as the events in the OADs do not conflict with what is in the manga, we can accept the ideas and concepts that are presented from the OAD to be cannon.
In the case of Himawari here the idea that CLAMP wants us to take out of what was in the 1st Rou OAD is that she is trying to move on after her attempt to advance her relationship with Watanuki had failed. We could see a future chapter that works off of this aspect about her, and if we do then we can accept that the idea is cannon, and possibly the event as well.