Then she needs to be following the custody agreement for her protection. Leniency is earned and he hasn’t earned it.

But again, none of this is your responsibility. You can decide to support her, knowing this is a struggle if hers she needs to work on. Or you can decide this is your deal-breaker and end things. Either is valid, so so what is best for you.

Right, but that’s not working, which is why I good next step for her would be to change the custody agreement. The open-door policy doesn’t work when one of the parties is behaving like this. A more defined agreement would allow her to say things like “per our custody agreement, you need to do XYZ. If you cannot, I will contact my lawyer”. So she has an additional layer of protection, you know?

It makes sense that you are re-evaluating the relationship since the ex is challenging to deal with and she’s struggling to maintain boundaries.

Before you jump to ending things, maybe consider supporting her into counseling. She’s struggling with boundaries and it’s probably coming from whatever awful history she was with her ex. Therapy can help her work through that. I’d also want her to get a more clearly defined custody agreement in place so she can have an additional buffer.

Now, it’s not your responsibility to put up with this or help her overcome whatever is going on, but love and support can go a long way for someone. Reflect on whether you can be that supportive person to her or if this is ultimately your deal-breaker. Do what feels right for you.