9 Warning Signs You’re In A Toxic Friendship That Can Harm You

Friendship Quality and Social Development (2002): https://www.purdue.edu/hhs/psy/directory/faculty/documents/Berndt_Friendship_quality_and_social_development.pdf
Jealousy in Close Relationships Among Emerging Adults (2014): https://dukespace.lib.duke.edu/dspace/bitstream/handle/10161/9039/Blomquist_duke_0066D_12532.pdf?sequence=1