How to help my friend, who's the long-term OW, see the light

[Amateurlifecoach]

My friend is younger than me and is just beginning to notice her own aged friends begin to settle down and get married. They are all late 20s/early 30s.She's really nice, friendly and outgoing and I would say, gets on better with men than women and works in a male dominated environment.
Im just setting the scene, not sure if it's relevant or not. She's not very confident and has made a few questionable life choices. She has low standards in her career and is coasting along without major ambition. She seems to be lacking in self esteem. She'd say, for example, "I'm not as good as you at....." whatever it may be.
She's always gone for much older men who seem to have baggage or have made bad decisions in there own lives.
I was pleased when she broke up with the last one and hoped a nicer man was in the future.
But it appears she's got involved with a married man. She's very secretive about it but it's been going on now for a long time, over a year, I think and she has said he is separated, but from some digging on FB, the wife doesn't seem to think they are.
Im not fully sure what my friend is telling me versus what he is telling her, but it's messy and I would love her to escape his obviously very charming clutches.
He's leading her to believe they have a future yet not appearing to be open about it. So having his cake and eating it, with lots of sneaking around and making my friend secretive, defensive and eating away at her confidence even more.
I'd like to help her see the light somehow. I know there's an MN script that cheaters follow. Is there a condensed version I can send her so she might read it and identify him and realise what his plan is. He probably has no intention of leaving his wife. And if he does, she won't be the last affair.
I hate that she is ruining her life with this waster and these should be the best years of her life.
She is stunning and doesn't realise it. She could have her pick of men her age who are available and she's also very engaging and great company. As her friend, is there anything I can do?

Anything you do is likely to have the opposite effect, especially if she has anger towards you because you are always better and cleverer and more right.

At the very most I would mention in passing the existence of the script. Then say nothing at all.

Maybe if you act like you think her choices are the best options for her, she will feel a natural compulsion to consider doing the opposite.

Did we ever get to the bottom of how the first poster knew it was her sister? It's been bugging me too!!!

I was the other woman once. To be clear, I make no excuses for my appalling behaviour.

I was traveling through a country with a friend, and as we were passing through City we met up with "Max", a boy I had a crush on as a teen whom I kept up periodic contact with. Max was our tour guide, showing us all around City and taking us out.

I fell very hard and very suddenly for Max. I knew he had a girlfriend and I didn't care; I even met her. I had met Max's best mate, his family, and everyone seemed to like me a lot more than his gf. This, in my own mind at the time, was justification. We kissed and declared love for each other. Then friend and I carried on our travels, and returned to home country.

Max made all sorts of promises: that he would post pictures he took while we were all together in City, that he had bought me jewelry and was going to send that, that he was going to move to my country (I was in uni, so I couldn't move to him). None of these things ever happened. Contact just faded away. Years later, he tried to add me on Fb. I saw from his profile that he had married the gf. I refused the request, and blocked him. No contact since then.

The point of me recounting this is that there was nothing anyone could have said to me that would have persuaded me not to carry on with him, or anything that would have stopped me from thinking that Max really was going to move for me. It took me a long time to get over it, but I did. I'm now engaged to a lovely man and we're expecting a baby.

My friend that I was travelling with was incredibly kind through it all, and this may be the best approach to take with your sister/friend.