I am so far only judging by other people's comments. From what I'm reading it sounds like the marriage was clear if you paid attention to the details that added up to the logical conclusion. I'm not sure if it was clear or not. It does sound like an unobservant person might have missed it.
Oh don't do a @Christopher (like he did with Batman Vs Superman) and judge the film (and comment on it at great length) on what others say. Go and watch it, not sure if you'll like the interaction, but some of the more suitable clues they're in a relationship are there and they are nice too see.
Maybe it had something to do with the German dubbed version I saw? They were using terms of endearment right from the point when Spiner woke up from the coma.
They were like that in the "Original" English version too.