I could have written that myself. I have BP, BPD and substance abuse problems too, and tons of other crap. Like you, I really can’t tell which of my symptoms are BP or BPD. I’m no dr but I’ll take a stab in the dark...

I would say that my mood swings (last a few min to an hour) are my BPD where as longer episodes of feeling down or major anxiety are my BP. As far as where the substance abuse comes from, I really don’t know because there’s a high likelihood in both disorders. Impulsivity is also a major issue for me. I blame a lot of that on BPD because I get like that no matter my moods. Also, both disorders are treated with similar meds. So yea I’d say it’s definitely hard to differ between the two. I’m not sure even the pdocs can tell most of the time.