Sit today and make a short list - of some actions which bring you satisfaction or joy. Dancing, singing, listening to music, walking on a nature trail; biking, team sports, personal pampering, the ocean, close proximity to water.
Just two or three notations, written so they may be read each day, will bring happy thoughts. Knowledge of what drives you, anticipation, that feeling of excitement which arises from looking forward to something. Remain aware of thoughts which divert you from pleasant ideas, reject them immediately.
Framing the mind's wanderings with positive, uplifting support is the first step toward lucidity, that 'wisdom which passes all understanding' -- and will provide peace and serenity, along with contented acceptance. All is as it seems . . . this happens solely in one's own domain.