This red flag should not be an immediate deal breaker. In this case, you need to determine someone intentions and your limits.
If someone is going through a hard time and still developing healthy coping skills, sometimes their boundaries become lacking and they forget about other boundaries. You can see if someone is truly remorse in how they apologize, acknowledging your hurt or whatever and stating why. We are human and are not perfect as article state us to be, so have some compassion for hurting people. We all fight battles, we do not talk about it. Sometimes people are hurting or do not know, this is not a crime.
If someone does not respect your boundaries deliberately, such as lying to you, belittling you or getting unreasonably angry for setting boundaries, then they have modus operdani 🙂 This is when you need decide to really reevaulate your relationship with this person. Remember we all go through hard times, most of us do not use our struggles to harm someone and if we do accidentally, we appologize and feel remorse. If someone does not feel remorse…then cut them off completely and document all interaction for self-protection.
. Remember manipulative behaviour can be for two reasons, to avoid someone feeling hurt and taking responsiblity for their own actions due to maladaptive narcissism or due to they have no real feelings to others. Depending on limitation and remorse of the manipulative individual who does not respect your boundaries and has no boundaries you can decided if you need to distance or cut off and your limitations.