Michelle had always dealt with what other people thought of her, because of the way she talked, looked, acted, and, eventually, because of who she married.
Being a black woman at Princeton was not the first time she had felt different, but it was a striking difference, nonetheless. It was as if people were always looking at her, judging her for the color of her skin or the way she was dressed. Even if some of it may have been paranoia, the fact was that she was black in a place that was predominantly white.
Most of the other black students at Princeton had the same experience, so they tended to stick together. To those on the outside, this could've looked like they were purposely excluding themselves, but it really wasn't like that. It was a way to cope with the fear of being rejected because they were different. Essentially, they were giving up without even trying, and Michelle knew it wasn't the best choice.
Michelle is one of those women who doesn't fit the stereotype. She had always seen herself taking the career path, but she also saw herself eventually getting married and having children. By wanting to do all of those things, she knew that, eventually, she would encounter more judgment.