Hi Ktgrn,
Welcome to bpdfamily You indeed have the right and responsibility to protect your child (and yourself) from harmful influences. Your mother's behavior sounds quite concerning, I am sorry you have been dealing with this for so long. I can imagine how horrible it must be knowing and possibly seeing that your mother cuts herself.
Has your mother been officially diagnosed with BPD? Has she ever gotten any targeted treatment/therapy for her issues including the cutting?
We describe some communication techniques on this site that you too might benefit from such as validation and S.E.T.:
ValidationExpress your truth - S.E.T.: Support, Empathy, TruthThese structured ways of communicating help minimize the likelihood of (further) conflict, while maximizing the likelihood of getting through to our BPD family-member. Following these communication patterns can also help us stay more calm ourselves. There are also other techniques described on this site, such as D.E.A.R.M.A.N. Were you already familiar with any of these techniques?
Sorry your mother has made it difficult for you these last 9 months, that is very unfortunate. But still, congrats on having your first child!

The Board Parrot