When is your big day?

Yesterday, a lovely customer who usually comes with compliments, came by. She suddenly asked me "when is your big day dear?" It caught me off guard. I smiled awkwardly and muttered that I don't know how to answer this question. Colleague probably overheard and said "soon.. soon.." I smiled at them and wished the lady have a pleasant day. I'm hardly in a stable relationship so why'd I even know when is my big day? Sometimes we get questions at the right time which somehow will make us realise what's our stand.=)