Responding to ungrateful

One person was desperate for a job. He had to shift from one city to another due to family reasons. In the new city being desperate he approached many friends. However, for two months he was without job and his family was suffering. Two of his friends went to this person and helped him to write a better resume. Then they gave strong recommendation letter with character certificate and work experience. This person got the appointment, and which paid him three times his expected salary. However, this person was not grateful to the two benefactors. He did not even call or text once to both his friends. However, the organization HR called those who recommended him and informed that they had appointed him.
Ungratefulness is a spiritual disease and social malaise. As believers, we come across ungrateful people all the time. It irritates, frustrates, and makes us hardened to other people needs and sometimes stops us from helping other any further. Lord Jesus Christ also experienced it during his ministry like the nine lepers who did not return. (Luke 17:17)
However, Lord Jesus Christ taught us that the Heavenly Father is kind to ungrateful and wicked. (Luke 6:35) If so, we as disciples should continue to do good even when people are ungrateful. Yes, we must plead to the Lord to help us to be kind to ungrateful and wicked. This is not going to be easy but have to discipline so as to grow into His likeness.
Another discipline is to do good and not expect any response from people. More the expectation, greater the disappointment. Hence, let us learn not to expect gratitude from people for any good we do.
Learning to forget the things we do for others is a good discipline. If those who receive help forget, it is not worth for us to remember either. God would remember if we have done all things that we do for the glory of God.
Do I do good without expectations and forget them?