Some people can’t change because guilt has a stronghold on them. Grace and mercy and forgiving yourself will fix that.
You may have to apply grace and mercy to your life over and over and forgive yourself over and over until you get to a place of acceptance. Or you could accept the grace, mercy, and forgiveness that is available to you at all times. You may think you can’t accpet it until you change completely and how is that working out for you? Change is a process and accepting grace, mercy, and forgiveness until the chains of guilt are broken is part of the process.
When you start to blame yourself, feel guilty, remind yourself that you are forgiven and you are covered by grace and mercy. You do not have to stay defeated. You do not have to live a defeated life because of guilt. You can move on. You can grow. You can enjoy this life.