Hi Bruinbelle88,
Not easy that she moved to the same city! Absence can make the heart grow relieved

What are some of the boundaries you're trying to set with her? How does she blow by them? People with BPD tend to not do as you ask, they do as they please. We have to be able to state our boundary and then enforce it, which is not easy with a parent.
Also, it sounds like she accuses you of not caring about her when she is guilty of not caring about you and your needs
My father is remarkable at doing this. It wasn't until I was in my 40s I realized he masterfully pointed out my shortcomings, I became distracted by those shortcomings, meanwhile his were worse and in plain sight and there was an unspoken rule they must never be addressed.
What is an example of a boundary you set, that she blew past?