怪我寡闻不知道你心里有人
[guài wŏ guă wén bù zhī dào nĭ xīn lĭ yŏu rén]
Expresses a regretful or slightly resentful recognition of not being aware of a situation, translating loosely as 'Blame my lack of insight, I didn’t know you had someone else on your mind.'