1) Fixates 1) Gets hung up 2) Hangs onto something 3) Is fixated 4) Is stuck on something 5) Overly preoccupies 
obsess, obsesses, obsessing 1. To dominate or preoccupy the thoughts, feelings, or desires of (a person); beset, trouble, or haunt persistently or abnormally: 'Suspicion obsessed him.' 2. To think about something unceasingly or persistently. 3. To occupy someone's thoughts constantly, compulsively, and exclusively: 'The desire for vengeance obsess...