I was diagnosed 6 years ago with bpd, at the time I was told I was an attention seeker and then it was forgotten completely. Because of this I've gone untreated. 

I have currently been in a relationship for over a year and the bpd is really starting to effect the relationship. 

Because of how I was treated when first diagnosed I just kind of ignored the diagnosis, so i havent told my bf that i have it. 

I want to tell him so he can understand me better but I'm really scared that he will think I've purposely deceived him, or he will leave me because of the stigma or not wanting to he involved with someone like me.

What should I do? If I should tell him how am I meant to?