The goal of this investigator-initiated single-site clinical trial is to compare the overall quality of life of participants taking Relugolix combination therapy (Rel-CT) following excisional surgery for endometriosis to participants that do not take Rel-CT following the same surgery. Rel-CT is an FDA approved form of medical treatment for endometriosis. It is known to work in treating endometriosis pain. However, investigators do not know whether or not there is a benefit to beginning Rel-CT immediately following surgery. This study will test if patients who take Rel-CT after surgery have better quality of life and less chance the endometriosis comes back, requiring additional surgery. The main question it aims to answer is: \- Does taking Rel-CT following excisional surgery for endometriosis result in higher Endometriosis Health Profile 30 (EHP-30) scores, indicating a positive impact on overall health-related quality of life and well-being? Participants will: * Be randomly assigned to one of two treatment groups. One treatment group will take study drug Rel-CT after having excisional surgery, and the other treatment group will just have the surgery alone. * Be asked to complete questionnaires, called the Endometriosis Health Profile 30 (EHP-30) at 4 timepoints. The first time is before surgery, then at follow-up visits at 1 month, 3 months, and 6 months. The survey has 30 questions that ask about pain, control, powerlessness, emotional well-being, social support, and self-image. Researchers will compare the two treatment groups (Rel-CT and non Rel-CT) to see if there is a change in EHP-30 scores.