Is the failure to complete the marriage a result of reciting Surah Yasin and supplicating for a specific matter that I regret, and how can I atone for this supplication?

Reading Surat Ya-Sin for the fulfillment of needs has not been reported in any tradition from the Prophet, peace be upon him. Wishing for something to happen and it not occurring is not a sin, as long as the wish itself is not forbidden by Islamic law. The servant must be content with Allah's decree when what they wish for does not happen, for Allah knows what is good and beneficial, and sometimes the good lies in what a person wishes for not occurring. A Muslim must submit to Allah's judgment, be content with His decree, have a good opinion of Him, and strive diligently in supplication.