多久了我等到的只是背影
[duō jiŭ le wŏ dĕng dào de zhĭ shì bèi yĭng]
'I waited for so long but ended up with just a back view.' This internet username reflects a person's disappointment after a long time of anticipation for something (or someone) and the feeling left is merely regret or a sense of unreciprocated love/expectation.