Comparing these two characters might seem difficult, but they really do share some significant similarities. First, Frederic and Holden are both caught up in difficult worlds not of their making and in which they do not belong. In their own ways, both are outsiders, but they struggle to function in their circumstances before finally leaving. Each of them then sets out on his own, making a journey.
Both Holden and Frederic experience a sense of isolation and loneliness, and both of them seek love and human connection to relieve those feelings. Frederic's relationship with Catherine and Holden's love for Phoebe are reflections of their emotional needs. Holden and Frederic are both deeply sensitive. Each has been touched by death, and both of them feel deep grief.