The phrase "complicated relationship" refers to a relationship between two or more people that is difficult to understand or deal with due to certain issues or problems. Full definition
Others are struggling with complicated relationships with romantic partners, spouses, or family members and hope to enhance these relationships. (psychologytoday.com)
Within this trend was another that spoke especially personally to me: the even more complicated relationship between mothers and daughters. (thefilmexperience.net)
They all become involved in complicated relationships with realistic issues. (lights-camera-jackson.com)