The concept referring to the idea that messages and feedback from others shape you into what you are today is called

Symbolic interactionism

Explanation:

Symbolic interactionism is the perspective that focuses on the relationship among individuals in a society, communication through the use of language and symbols among individuals. Symbolic interactionist suggest that society is composed of symbols that people use to establish meaning, communicate with one another and develop their view of the world, it is the idea that suggest that what an individual becomes is as a result of messages and feedback and interactions with others.