A follower of Jesus weighed down with guilt is carrying a burden imposed by Satan, no matter the human source (yourself or others).
When Jesus died on the cross, He took our sin and gave us His righteousness, justifying us before God. That means that there was nothing I could do to set myself right with God - which is why Jesus had to die. It also means that because Jesus does everything perfectly, He took my sin away perfectly and gave me His righteousness perfectly.
I see people in my office (and I myself struggle with this at times) who are laden with the guilt burden over choices they made in the past. That burden can be brought to their mind by similar circumstances, physical reminders, times of the year, or any number of factors. But it comes and, when it does, comes with a crushing weight.
The Good News for followers of Jesus: you don't have to bear that load. Jesus has already borne it for you. Release it to Him (again and again and again) as often as you sense its weight. You are not forgiven because you confess - you are forgiven because Jesus died and rose again.