By forgetting the past and by throwing myself into other interests, I forget to worry.

Dempsey frames worry as something sustained by rumination—replaying what has already happened and projecting its consequences forward. His remedy is practical rather than philosophical: deliberately disengage from the past and redirect attention into “other interests,” i.e., absorbing work, hobbies, or goals that occupy the mind and body. The line implies that emotional resilience can be trained through focus and substitution: you cannot always control events, but you can control where you place attention. Coming from a fighter associated with discipline and recovery after setbacks, the quote also reads as advice for coping with defeat or hardship by returning to purposeful activity instead of self-reproach.