He is sinful and is being lured by the glamor of this Dunya. Leaving him is not the best solution as you need to win his heart once again by being devoted, caring and loving to him in a way that he can’t find anything faulty in you. Such care and love will make him like a ring
round your finger. Bit by bit, you should try to make him focus on praying on time and realizing what pleases Allah from what angers Him. Slowly, he will in sha Allah become better.