If your boyfriend still has an ex-girlfriend in mind, it's a complex issue that requires both of you to communicate openly and find a solution together. Here are some suggestions:
Communication: Be open and honest with your boyfriend about your feelings and concerns. Tell him that you still have concerns about his ex-girlfriend and ask him what he thinks and feels. Respect his feelings and also express your needs and boundaries.
Understanding his past: Everyone has a past, including a previous relationship. Try to understand the past of your boyfriend and his ex-girlfriend and why they broke up. Knowing the reason and timeline of their breakup can help you better understand how he feels.
Build trust: Trust is very important in a relationship. If your boyfriend and his ex-girlfriend are not dealing with a past relationship, then you need to build trust with him. It takes time, but you can work together.
Give him space: Sometimes, people need some time to process past emotions. Give your boyfriend some space and time to process his or her emotions while also showing your support and understanding.
Seek professional help: If you are unable to solve this problem, or if the problem is causing a lot of distress to your relationship, then consider seeking professional help, such as a counselor or a marriage and family specialist. They can help you find a solution to your problem.
In conclusion, having an ex-girlfriend in the heart of a boyfriend is a complex issue that requires both parties to communicate openly and work hard to solve it. Through understanding, trust, and space, you can overcome this together and build healthier relationships.