I used to be a righteous person 😔

Back in high school, I was trying my best to be pious, like avoiding looking at my non-mahram teachers. I felt this beautiful spiritual light inside. I’d pray with so much devotion and make heartfelt dua. Now, even though I’m about to become an Islamic scholar next year and I know Allah Subhanahu wa Ta’ala can forgive all sins, I’m completely distracted. I feel so much shame, I can't even bring myself to stand before Him. I know I should repent, but I keep falling into sin. I honestly hate myself right now...