>>618082"A cuckold (sometimes shortened to cuck) is the husband of an adulterous wife"
Has turned into:
"cuck: used in the context of 'marriage' mostly; more specifically; as a submissive husband to a dominant wife or spouse, girlfriend, etc. "
And is used on 4chan as a word for being willfully dominated by just about anyone. But in this case, it's extremely related since it's a fiance situation.
I shouldn't have to explain this to you.