BPD Parent Indifferent to No Contact

Has anyone decided to go NC and their parent acted totally indifferent?

About a year before going NC, I began to set boundaries and explain the issues in the relationship. I was clear and specific about what was unhealthy and what would need to change for me to move forward.

The cycle during that time was: (1) I would set a boundary and/or explain why something has hurt me (2) BPD mom would give a generic/incoherent response and/or ignore me for a few months or weeks (3) BPD mom would eventually reach out as if nothing happened to give a mundane update on herself or report on someone elses crisis/tragedy (3) I would restate the boundary and issue, and the cycle would repeat

Once I saw that there was no way BPD mom would/could work on the relationship, I explained that I was going NC and why. Her response was essentially "k sounds good", followed up by "accidentally" sending me a nonchalant text meant for "someone else" to make plans later on. (This "accidental" message thing seemed to happen often - anytime BPD mom felt rejected/abandoned).

I'm curious if anyone else has experienced this? It was almost as if she immediately responded by acting like I had never existed and she didn't care, then ended the convo as quickly as possible so she didn't have to think about it.

(In the past her MO has been rage, but obviously not the case here).