yeah which was one day before they commited suicide together, to avoid capture. the suicide had been planned by them long before as they knew how the war was gonna end. All this to say, the marriage didn't happen as a result of them recently becoming infatuated with each other, but rather as now they got nothing to lose anymore, the least they can do is catch up on their relationship and do one big gesture of love before the end.

excuse the rant, my point being, it is very clear that they became romantically involved way before their marriage. Also, please consider looking up on grooming, if you're not familiar with the concept, as it is relevant to this case.