Suspect I might have BPD

Hi, i am a 19 yr old female, i've suspected that i have bpd for a few months now and am going to ask my therapist if they can get me tested soon.
i relate a lot to all the symptoms of bpd except i can control my impulsive thoughts when theyre extreme, i tend to fall into long-term self-destructive habits so i always have a vice to lean on at any given time (smoking, dr*gs, alcohol, eating disorders etc).
my biggest issue is with friendships and fear of abandonment, i felt like the one whose "less wanted" in any group, like it wouldnt make a difference whether or not i was there, a lot when i was a child. now ive been in a friendship group for a few yrs and realised my self worth relies mostly on what i think they think of me and it becomes unbearable if i dont get validation that they like me. the worst examplesof this are times when ive got very drunk i end up shouting at them that they dont like me or care for me. im surprised they've stuck around this long but i keep telling myself i need to stop feeling this way. when everythings okay i feel like theyre the best people in the world, like platonic soulmates or something, but the slightest unexpected action/facial expression/comment/lack of attention sends me right back to thinking they hate me and are just keeping me around because i havent given them a big enough reason to end the friendship. sometimes i think i should just give them one so i can relieve them from having to be around me or i get suicidal thoughts because im scared that it wont matter who im friends with this will always keep happening.
when i think somethings off i jump to conclusions and always think the worst of them. i dont want them to get sick of my lack of trust and accusations because i do love them a lot but in those moments its like i dont know what to believe and maybe the whole friendship was a lie.
every time this happens i will try to be upfront with them and just ask whats going on but i dont know if im being emotionally draining and i dont want to be that person that needs reassurance 24/7.
whether i end up being diagnosed or not, i was wondering if anyone has any advice on how to not ruin friendships because of feeling like this?
apologies if this is the wrong topic to post this on, i thought it was most appropriate as im not actually diagnosed.

Hello, and welcome!

Just a note that I moved your post from the thread you posted to- as a first time poster and the detail of it, I felt it deserved its own thread.

Do you tend to be like this in romantic relationships, as well? If you mentioned that, I missed it.

I don't believe myself to be BPD, but I do see some Borderline tendencies in myself. I empathise with you on a... not constant, but a nagging conviction that in any group, I am one who wouldn't be missed, that no one cares about me. I don't dwell on it, or obsess over it, I just feel it, in my more self-aware moments. I don't tend to seek validation, but if I let myself, I'd get caught up in thinking that no one really likes me- I don't think they do, in fact- from my partner, to extended family, to friends, what of those I have. So yes that part resonates with me.

This is pretty common I think in those with BPD, but probably those that don't have it too.

For me I think the key was spotting my triggers and actually just deciding I am not doing that any more, pushing people away. When it happens, as it will, I remind myself this is just my BPD brain going off on one again so I am going to ignore it. And yes I do tell my brain where to get off too.

Other times the delaying tactic is a good one. If I feel the same way in x days or hours or whatever then I will act on it. And generally once the BPD brain shuts up I don't want to end the friendship at all. And I will also be very glad I didn't act on those feelings and do or say something stupid.

Actually journalling helped me with this. When I feel wound up or whatever instead of rowing with a friend I just spill in the journal. Doing that, gives me the chance to stop and think and most times I realise I am over reacting or being daft or whatever. And it's only my journal that knows this. So I can say what I like without feeling silly and I probably avoid a row.

Sometimes I write those letters you don't send. So I say all the stuff I wanted to say to that person. And then I delete it. It helps to get my feelings out without damaging any friendships.

You may not even have BPD. But worth having an assessment if you're worried about it.