Me and my ex have been broken up for almost 3 years. But I still think about him a lot?

Thinking about your ex is common even after 3 years. For a period of time in your life you had a special bond and relationship with him. You invested in each other and it sounds like you cared deeply for him. As you experience new events and people in your life those thoughts can become less and less frequent. You can still honor the positive parts of the relationship by being thankful for happy memories and thankful for difficult times that you have learned from. What would you say is a valuable lesson you gained from your time with him?