Don’t hate yourself! Once you’ve done teshuvah — felt remorse, asked forgiveness, resolved not to do it again, and really didn’t do it again — there’s nothing to be ashamed of! Teshuvah actually rectifies the past. It is even taught that it turns sins in merits. So the effect on your neshamah really has been reversed. When you remember what you’ve done or seen, don’t beat yourself up about it — just remind yourself that everything has happened for the good, and thank Hashem for allowing you to do teshuvah. If you like, pray in your own words (including doing teshuvah and asking that any potential lingering negative effects be eliminated) for a few minutes each day, and then as (as Rebbe Nachman teaches) be happy the rest of the day. Here are a couple relevant quotes:
“God’s greatness is unfathomable: that is why Teshuvah has such power. No matter how far you may have fallen – be it to the lowest depths – never despair, because you can always return to God. With just a little effort you can turn even your worst sins into merits. No matter where in the world you fall, you can easily come back to God. This is because of His unfathomable greatness. Nothing is beyond His power. Just never give up! Keep crying out, praying and pleading to God at all times.” Sichot Haran #3
“You should tell God everything you feel, be it contrition and longing to repent over the past or requests and supplications to come truly close to God from now on, each person according to his level.
Be very careful to get into the habit of spending time every day on your personal prayers and meditation. Fix a regular time for this and then be happy for the rest of the day!” Likutei Moharan II 25