disillusion
verb [ T ] uk/ˌdɪs.ɪˈluː.ʒən/ us/ˌdɪs.ɪˈluː.ʒən/
使幻想破灭;使清醒，使觉悟
to disappoint someone by telling them the unpleasant truth about something or someone that they had a good opinion of or respected
I hate to/I'm sorry to disillusion you, but pregnancy is not always wonderful - I was sick every day for six months. 我不想打破你的美梦，但是怀孕并非总是美妙的事——我当时有6个月的时间天天都恶心。