Seeks
I understand how that conversation might not have gone over well.
Since there is a tremendous amount of information on this website I thought I would point out this link which might be helpful to you.
Getting a "Borderline" into TherapyThis is from that link.
Professionals do not recommend that you tell a loved one that you suspect that they have Borderline Personality Disorder. We may think that our loved one will be grateful to have the disorder targeted and will rush into therapy to conquer their demons, but this usually doesn't happen. Instead, this is difficult advice to receive and more likely to sound critical and shaming (e.g., you are defective) and incite defensiveness, and break down the relationship trust. It's not like a broken leg where the affliction is tangible, the cure is tangible, and the stigma nonexistent. While we are grateful to learn about the disorder and the pathways to recovery - for us the information is validating and represents a potential solution to our family problems- to the afflicted, it is shaming (you are defective), stigmatizing (mental illness in general, Borderline Personality Disorder specifically), and puts all the responsibility for the family problems on the loved one's shoulders
For my partner is was the responsibility part that was hardest, she struggled to be responsible for that much of the relationship. Which I can appreciate, I don't want to be responsible for 90% of the relationship either.
'ducks