Hi Ellisen and welcome to BPDR!

You're not alone. I lost four of my five closest friends when I was at my most "borderline", because they couldn't cope with my mood swings, self-harm, anger, impulsive behaviours, etc. One of them is now a good friend again, but the other three are gone from my life. For a long time I felt that only people with similar MH problems could possibly like and understand me. But now, a few years on, I'm 90% recovered and have some fabulous friends with and without MH issues.

Anger and impulsivity and finding your buttons get pushed easily definitely can be BPD symptoms, they can also be symptoms of other things as well of course. For a diagnosis I would definitely recommend talking to a psychiatrist and/or therapist - are you getting any professional help at the moment? You're welcome here regardless of diagnosis though. The "tools" (which you can find in the box at the top left of every page) are great for anyone who wants to improve their mental health, and quite a few members (including myself) don't have the BPD label.
You sound really lonely right now and I hope connecting with people here can help you feel less alone.

Again, welcome!
Lirael