@Link,
Try not to forget that excessive shame can draw a person away from their spiritual pursuits. This can be exploited by dark forces. Try not to dwell on your faults. They happen in an impulsive moment.
God created us with animal impluses. It is natural to act on them. Natural, but not nessessarily healthy. Developing impulse control takes time, patience, and faith. Shame diminishes faith, makes us impatient, and makes it harder to break bad habits. Sometimes shame can be a useful tool, but, for you, it seems like it is interfering.
My advice for you is to continue to focus on God's mercy, but to take it to the next level. Emulate this mercy and apply it to yourself. Have compassion on yourself; appreciate your inborn talents, and forgive your animal impulses when they happen. This will give you space to refocus on your good traits and future goals instead of focusing on the past.
