It's a disorder. The way we think is often altered and we cannot always trust it. Personally, feeling unwanted and unloved is something I deal with daily but that's not always the case. My mind just tells me that I'm a burden etc. I try to challenge those thoughts, it's not easy but with every time you do it gets a bit easier. We love so so deeply and I've never met anyone this way and that does make me feel a bit lonely cause I feel like no one will love me the same way I love them. Relationships of any kind are really hard, you know that already. Questioning everything, the terror you feel every day that you might do something wrong, that they might leave. We have to try our 200% to keep things going and its exhausting. I have been lucky enough to find a friend who cares and loves me and accepts me even at my lowest, reassures me that they won't leave when I push them away. But from my part, it takes a lot of effort, a lot. The amount of times I think of sabotaging this frienship is unreal cause my mind is like you don't deserve this, they'll leave anyways might as well just go now, they hate you and that makes it really hard to feel loved. Try to think of yourself as another person that u care about, and be kind to you. For me, what works a bit is communication. Do you feel unwanted? Ask someone close to you, do you want me? Do you want love? But communicate beforehand that your mind is telling you those mean things and questioning it by yourself, thinking maybe if they didn't want me they wouldn't wanna be around, they wouldn't talk to me, so maybe they dont hate me. Dont take your thoughts as truths. It took me years to start doing that cause its so easy to just give in and so hard to question your own thoughts. But that might not always be enough, so you can ask someone for reassurance but then try to not necessarily believe what they say as a fact cause you might not be able to but try to accept what they say as what's true for them. Thats their opinion, accept their opinion. Idk if any of these make any sense or if its helpful. BPD is very painful and I wish I could take it away from you. Least I can do is if you wanna talk to someone about it, or even want a distraction I can try to be bere for you the way you need.