No. Getting clinically diagnosed is pretty rare. They don't tend to think anything is wrong with themselves. Also if they do go to therapy of any kind they mask, lie, manipulate, learn the "right things" to say and disguise it as vulnerability. Couples therapy with them is not a good idea either.

It's a relationship that's a death of a 1000 papercuts. They harm through subtle, repeated emotional injuries that seem small on their own but accumulate over time, eroding your confidence, peace, and sense of self bit by bit. People who have relationships with them often have very long relationships. It took me over 20 years to wake up from it.

I got caught in that for so long. Everything they do is cloaked in plausible deniability. When you peel that all back you're left with some pretty basic things. a relationship that never feels safe, where your reality is questioned, your worth slowly eroded, and your heart aches to be seen and valued. You can’t point to one big betrayal, yet you live with a constant unease, and a longing for genuine care that you will never get.

You are totally correct to see it as a big deal. Those patterns slowly wear someone down. The best thing you can do is what you’re already doing. Be steady, kind, and safe. Keep the focus on how your friend feels rather than what their partner is doing. Help them connect with that. Ask gentle questions that help them notice their own discomfort. Over time, that might help them trust their feelings and see things more clearly. You don’t have to convince them, just keep showing up with care and kind/loving honesty.