While it's difficult to draw definitive conclusions without knowing all the details and dynamics of your past relationship, there are some red flags in this situation that you should be aware of:
Emotional infidelity: If your ex is in a new serious relationship but is still engaging in a physical relationship with you, it can indicate emotional infidelity. Emotional infidelity means that she may be emotionally committed to her new partner but is still maintaining a physical connection with you, which is not fair to anyone involved.
Lack of boundaries: Engaging in a physical relationship with an ex while being in a new serious relationship shows a lack of clear boundaries. Healthy relationships require respect for the emotional well-being of all parties involved, and this behavior suggests a disregard for her current partner's feelings.
Pattern of behavior: If this has happened with her last two boyfriends as well, it could indicate a pattern of behavior. It suggests that she might have difficulty fully letting go of past relationships or has a tendency to seek comfort or validation outside of her current partnerships.
Communication issues: Open and honest communication is crucial in any relationship. If your ex is not transparent about her actions or intentions with you or her current boyfriend, it can be a sign of communication problems and dishonesty.
It's essential to recognize that every situation is unique, and there may be underlying reasons or complexities that you're not aware of. However, regardless of the reasons, this kind of behavior can be harmful to everyone involved. If you still have feelings for your ex, it's crucial to consider your own emotional well-being and whether this situation is hindering your ability to move on and find a healthier relationship.
If you are uncomfortable with the current arrangement or suspect that she was cheating on you during your relationship, it might be best to have an open and honest conversation with her about your feelings and concerns. Remember that you deserve to be in a relationship where you are respected and treated with honesty and integrity. If this situation is causing you pain or preventing you from moving forward, it may be necessary to establish clear boundaries and distance yourself for your own emotional well-being.