I dealt with someone for a year and a half who, on the basis of the list of symptoms you cited, either has it or displays very similar traits. (I'd also say she has about 7 of them.) She is about 20 and was a little younger when I was involved in her life and I think it's still young enough to be uncertain about how someone's personality will solidify - and of course I'm not a trained psychologist. In MBTI terms I'm pretty sure she's either a withdrawn ENFP or an aggressive INFP.
I was trying to more or less befriend/mentor her but it turned out quite an unpleasant experience. She was very very jealous of me having any other friendships and either loudly proclaimed her jealousy, or tried to introduce herself into all my friends' lives (or at least, those dumb enough to friend her on FB, after I warned them...) and act as though she had friendships with them which were the same as the friendships I'd built up over five, ten or fifteen years. She wasn't able to comprehend things like personal boundaries, though I spelled out to her in harsh detail what I considered personal boundary violations, and she would do things like follow me down the street and jump onto public transport with me although I had told her the conversation was over and to go home - as well as grabbing hold of me and refusing to let go, etc. She also adopted my interests as her own - I realised gradually that there had been a woman before me (who I knew slightly) who she had done the same thing with, glommed onto extremely and started imitating her life. In both my case and the case of the woman before me it seemed like she considered us combination best friend/mom/big sister/lesbian crush/person to be imitated in every detail. Actually, I noticed that with a few of my friends she'd friended on FB she was imitating their style, interests etc in various ways too (they also noticed and mentioned it to me). It seems like an emptiness which pushes her to try to take a personality from others - she even talked to me about feelings of emptiness, not existing, needing to take things from others, etc which are all associated with BPD.
I've basically removed her from my life as I was unable to deal with the situation, after trying very hard. I didn't just cut her off - I made it very very clear, in a lot of detail, that I had tried and tried to have a semi-normal friendship with her, that I had given her many warnings that the situation was unsustainable, and that I was ending the friendship because her behaviour was so utterly unacceptable and destructive to me. She lives at home but her family is very dysfunctional and she doesn't get support, although other friends have offered various types of support (and I made them very aware both that she needed support, but also that I was no longer able to offer it). I found her extreme ingratitude and sense of entitlement hardest of all to deal with, honestly. She was very manipulative and I gradually realised that she was trying to keep me in her life, and make me put up with intolerable behaviour, by constantly promising to change.
I think the best thing I did was push her to get into therapy, but I'm not sure she's still doing therapy. We attend the same place of worship so we see each other occasionally though I don't see her much there these days. But I don't even say hello if I can avoid it because she's still showing some stalker-like behaviours. She's pursuing some of my friends in various ways and she just started studying at uni - pretty much exactly what I studied many years ago, which is definitely no coincidence. She is basically leaving me alone though which is a big relief. I have also warned my friends to be careful about interacting with her. I really got the impression with one of my friends in particular that, because this girl finally realised that her friendship was me was over, that she was trying to replace me with my friend (who has a lot of her own difficulties in life right now and REALLY doesn't need that.)
I probably sound quite harsh in this but it was a difficult experience and I don't think I was strong enough. I'm pretty sure she's mentally ill, whether BPD or otherwise, but what I found nastiest was just that she seemed to feel it ok to inflict a horrible, ungrateful, nasty personality on everyone else - especially someone who really tried to help, like me. And that's something outside of BPD - it's how she was choosing to behave. She's a very angry, aggressive, spiteful, bitter, negative person. I think anyone who deals with a friend or acquaintance with such problems needs to maintain rock solid boundaries (something I'm not historically good at, but this experience did help with that - I learned a lot about maintaining boundaries) and be prepared to say "no" constantly. The best thing to do is probably to encourage them to get professional help. And if you've done all you can and it's overwhelming, don't be afraid to remove yourself from their life. You can't save other people.