Some people tend to express guilt when others do things for them. You will hear them saying things like, "I feel guilty for having bothered you." "I am so sorry that I made you go out of your way." "I feel bad for having taken your time." "Please forgive me for your having to do this for me."
People who have this pattern are often sensitive people who don't want to cause others any distress or unpleasantness. At times they could use a boost to their self-image. By realizing that they have infinite value and worth because they are created in the image of the Almighty, they will increase their realization that they deserve the kindness and goodness that others do for them.
When someone goes out of their way to do something for you or helps you in any way, express gratitude rather than guilt. When you say, "I am so very grateful for all the effort you put into this," or "Thank you greatly for having done so much for me," you experience the positive energy of feelings of gratitude. And the person you are telling this to will experience positive energy for being appreciated.
(From Rabbi Zelig Pliskin's book: Thank You! Gratitude: Formulas, Stories, and Insights: Artscroll Publishers)