autoengañarse

A very common, everyday verb for refusing to accept an obvious truth about oneself or one's situation — self-delusion, often used as gentle or harsh advice: deja de autoengañarte.

• Se autoengaña si cree que la relación va a mejorar sola. — She's kidding herself if she thinks the relationship will improve on its own.
• Deja de autoengañarte, ese negocio no es rentable. — Stop deceiving yourself, that business isn't profitable.
• Es fácil autoengañarse cuando no queremos afrontar un problema. — It's easy to deceive yourself when you don't want to face a problem.

Learners often reach for engañarse a sí mismo, which works but sounds redundant — autoengañarse is the natural single-word form native speakers actually use.

Often confused with engañar.