Some more stuff from wikipedia:
Lépine was uncommunicative and showed little emotion. He suffered from low self-esteem, exacerbated by his chronic acne. Family relations remained difficult; his younger sister Nadia publicly humiliated him about his acne and his lack of girlfriends. He fantasized about her death, and on one occasion made a mock grave for her. He was overjoyed when in 1981 she was placed in a group home because of her delinquent behaviour and drug abuse.
He was seen as nervous, hyperactive, and immature by his colleagues. He developed an attraction to another employee, but he was too shy to act on his feelings. After a year at college, he switched from the university-destined science program into electronics technology, a three-year technical program geared more towards immediate employment. His teachers remembered him as being a model student, quiet, hardworking and generally doing well in his classes, particularly those related to electrotechnology. There was an unexplained drop in his marks in the fall 1985 term, and in February 1986, during the last term of the program, he suddenly and without explanation stopped attending classes, as a result failing to complete his diploma.
Lépine wanted a girlfriend, but was generally ill at ease around women. He tended to boss women around and show off his knowledge in front of them. He spoke out to men about his dislike of feminists, career women and women in traditionally male occupations, such as the police force, stating that women should remain in the home, caring for their families. Lépine applied again to the École Polytechnique in 1989; however his application was rejected as he lacked required courses. In March 1989 he abandoned the course in computer programming, though he performed well in the CEGEP course, obtaining 100% in his final exam. In April 1989 he met with a university admissions officer, and complained about how women were taking over the job market from men.