Thank you for the added information. It helps a lot. I believe I can now be of help with this issue.
I can imagine how worrisome this situation must be for you. I need you to understand that I can't give you any statistical information. There have been no studies conducted on the personality types of people attracted to people with enmeshment issues, let alone large scale studies that would be able to give such figures.
But I can tell you from my experience as a psychologist working with people in therapy and answering thousands of questions from people all over the world:
Your real concern is not that he has enmeshment issues as well. That's not as common. Your real concern is that he tends toward being narcissistic. What do I mean?
Enmeshment issues (EI) refers to having boundaries that aren't functioning efficiently: being so personally involved in the other person and their issues, etc. that the person's "self" is not separate from the other person in healthy ways. Rather than complementing the person, the one with EI tends to get swallowed up into the other person emotionally.
Narcissistic people are emotional "swallowers" of other people. They have no sense of the other person's boundaries, only their own. And so they tend to attract people who have EI. This is of concern. Because they can be very rigid and controlling people.
I can't say, of course, anything about her boyfriend as I know nothing about him. But I can tell you that in psychological practice, this is the greater concern.
Okay, I wish you the very best!
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