Excessive social media use is associated with several adverse psychological outcomes, including psychological distress and lower levels of self-esteem. Research reports that feelings of loneliness enhance social media abuse, with individuals reporting stronger engagement in social media. However, self-esteem and self-compassion, considered complementary constructs, mitigate social media use. This research explores the association between social media and loneliness and how self-esteem and self-compassion may vary. A sample of 426 Greek adults fulfilled the first adapted version of the Social Media Disorder Scale to assess social media addiction, the UCLA loneliness scale, Rosenberg’s self-esteem scale, and the Self Compassion Scale. Structural equation modeling was used, along with Analysis of Variance, to estimate the role of demographics in excessive social media use, such as gender, education, age, and the number of followers. Results revealed that self-esteem was not associated with social media use or other behaviors. Loneliness was positively associated with social media use. Alternatively, higher levels of self-compassion were associated with lower social media use. Self-compassion acted as a mediator with individuals feeling loneliness and exhibiting lower levels of social media addiction. Possible explanations, future directions, and factors contributing to the insignificant relationship between self-esteem and social media are discussed.