how does existential/ humanistic theory apply to this case?

Jack works in HR for a large international organization. He is becoming more and more stressed at work as the company is constantly changing and evolving. It is a requirement of his job that he keeps up with this change by implementing new strategies as well as ensuring focus is kept on his main role of headhunting new employees. He finds that he is working twelve-hour days, six days a week and doesn't have time for friends and family. He has been promoted annually since beginning at the company and received quarterly bonuses for performance. He carries a work cellphone wherever he goes and his bosses call and text frequently.He has begun having trouble sleeping and got in a minor car accident the other day when his work phone rang while he was driving. He has started yelling at staff members when they ask questions and when making small mistakes in their work. Concerned about his stress levels, Jack's primary care physician referred him to therapy.