How can I help someone else in a similar relationship?

[VIDEO: "What is parental alienation?"]

So, the only person I've told most of the story about my uNPDexbf is actually one of my colleagues, with whom I've become friends. He has told me that he is increasingly worried about his niece, a girl who is about my age (early 20s) and has been recycling her relationship unhappily for several years - basically what I did for all my late teens. A lot of it sounds like the same stuff I went through: the recycling, the being played off against other people, the emotional abuse, and for this girl the first incidence of physical abuse led to their last breakup. But she wants him back.

Today, when she called my colleague in pieces, he actually put her on the phone to me. I told her a bit about what I experienced, but added that I understood that nobody could ever make me see that the relationship was broken, that I had to see it myself. I suggested that she take a step back, keep herself out of it for a few weeks and see how she felt after some distance, because I felt that if it had been me I would never have responded to 'THIS GUY IS PROBABLY SATAN, LEAVE NOW.' So I said to her what someone said on here lately: your baseline of what is normal changes, so what would the 'you' that you were before the relationship think of your feelings now? (I think this is hard at our age though. I would very likely always be a different person at 21 than I was at 17.)

I gave my colleague some info on NPD, and asked him if it sounded like what his niece was dealing with. I told him it was probably a bad idea to mention personality disorders, but that for me, realizing that what I was facing would actually be classed as 'abuse' totally changed how I felt about the relationship. But I warned him that trying to drag her away might alienate her entirely and that it would be harder for her to leave without her support structure around her.

So I'm going to ask on his behalf; what things can he say that might give her some perspective without driving her off and making her hate him? Is bringing up the word 'abuse' just as bad as talking about PDs? Would it work for him to say 'I will love and support you whatever your decision, but I think that this relationship is really bad news for you. It shows a lot of the characteristics that you commonly see in abusive relationships and whilst I can't choose what is okay for you, it concerns me.' ?

[Red Sky]

So, the only person I've told most of the story about my uNPDexbf is actually one of my colleagues, with whom I've become friends. He has told me that he is increasingly worried about his niece, a girl who is about my age (early 20s) and has been recycling her relationship unhappily for several years - basically what I did for all my late teens. A lot of it sounds like the same stuff I went through: the recycling, the being played off against other people, the emotional abuse, and for this girl the first incidence of physical abuse led to their last breakup. But she wants him back.

Today, when she called my colleague in pieces, he actually put her on the phone to me. I told her a bit about what I experienced, but added that I understood that nobody could ever make me see that the relationship was broken, that I had to see it myself. I suggested that she take a step back, keep herself out of it for a few weeks and see how she felt after some distance, because I felt that if it had been me I would never have responded to 'THIS GUY IS PROBABLY SATAN, LEAVE NOW.' So I said to her what someone said on here lately: your baseline of what is normal changes, so what would the 'you' that you were before the relationship think of your feelings now? (I think this is hard at our age though. I would very likely always be a different person at 21 than I was at 17.)

I gave my colleague some info on NPD, and asked him if it sounded like what his niece was dealing with. I told him it was probably a bad idea to mention personality disorders, but that for me, realizing that what I was facing would actually be classed as 'abuse' totally changed how I felt about the relationship. But I warned him that trying to drag her away might alienate her entirely and that it would be harder for her to leave without her support structure around her.

So I'm going to ask on his behalf; what things can he say that might give her some perspective without driving her off and making her hate him? Is bringing up the word 'abuse' just as bad as talking about PDs? Would it work for him to say 'I will love and support you whatever your decision, but I think that this relationship is really bad news for you. It shows a lot of the characteristics that you commonly see in abusive relationships and whilst I can't choose what is okay for you, it concerns me.' ?