This VeryWellHealth.com article by Angelica Bottaro is a great refresher (or primer if you are just learning about BPD) on the triggers of Borderline Personality Disorder. Knowing the possible triggers for someone who is living with BPD, what an emotional episode might look like, and potential coping mechanisms can be immensely helpful for family members or friends of those who have Borderline Personality Disorder. This article is well organized with lists of triggers and coping mechanisms and could be a handy resource, like this example:

“People who cope with BPD often go through times of normalcy that are broken up by episodes. Everyone has unique triggers because each person is different, but one common theme among many people with BPD is the fear of rejection or abandonment.

To cope with the illness, it’s important to recognize triggers so that you can avoid them when possible. When symptoms do arise, seeking help or practicing self-care techniques may help you manage the symptoms and avoid overindulging in unhealthy behaviors.”

You can read the full article here