Vampires do not need to abide by damn mortals and their Aedric deities! Common sense, Beth! But I guess trolling the fans is amusing

/
Lol, yeah. Especially considering she was likely around before the Divines even became a religion in Tamriel. The very fact that she is surprised when you mention a Cyrodilic Empire is a testament to her age. We're talking about a woman thousands of years old in the form of a 20-something year old. I highly doubt she'd be interested in mortal concepts such as romance, other than as a means to manipulate. Not to mention the whole fact that she got screwed by Molag Bal.
Also, prior to the whole "Divines" concept, the Nords didn't believe in "marriage". Simply being with and living with their loved one was enough. They didn't need nor care for the whole pomp "marriage" ceremony/contract. If you ask me, the real world can learn a lesson from that.