What are some actionable steps I can take to overcome my "Nice Guy Syndrome"

Basically this "Nice Guy Syndrome," as described by Dr. Robert Glover, refers to a pattern of behavior where individuals, often men, seek approval and avoid conflict by being overly nice, accommodating, and putting others' needs before their own. Ofthen, nice guys are seen as doormats/people pleasers and end up building resentment, unfulfillment, and difficulty in forming genuine connections. From a Buddhist perspective, which teachings or principles can help in understanding and addressing the root causes of this syndrome? Furthermore and more importantly, what are practical, small, and specific steps that I can take to gradually overcome this pattern of behavior and develop healthier relationship dynamics? I know general mindfulness helps, and probably alone is enough to fix it overtime, but I am looking for something more doable and more direct. Thanks for any answers