Hi protomartyr and welcome to bpdfamily
Thanks for introducing yourself to our online community
Having a BPD mother can definitely be quite challenging, many of our members can attest to that as you've probably already gathered from the posts you've read here.
Your mom was diagnosed with BPD, did she get any kind of targeted treatment after receiving this diagnosis?
Anger is something many of our members have struggled with. It's natural to feel anger and learning how to deal with our anger in a constructive manner is an important part of the healing process.
Lately some of it's starting to leak out... .
Did anything in particular perhaps happen recently leading to your anger leaking out?
... ., mainly in the form of being too quick to get angry with my wife when something she does vaguely reminds me of mom. My wife and kids and I have been in family therapy for a while now, and I only just recently told her about my mom's BPD and the abuse I suffered from her. Since denial and avoidance are clearly not working out for me, here I am.

Being able to identify one's triggers is also very important. I am glad you are able to recognize that your mom's abuse of you is still affecting you now as an adult. Do you feel like your family therapy has been helpful so far?
You've only recently told your wife about your mom's BPD and how she abused you. How did your wife respond to this?
Take care
The Board Parrot