My partner maintains contact with an ex-lover (he was married and still is) she has known for 25 years. They have not been physically intimate for 16 years, but she did meet him secretly while married 5 years ago and kissed. She divorced 4 years ago, and he started inviting her and a girlfriend to his ski lodge. They talk several times a week, and she values their friendship. The calls are still personal, though she says he's harmless and that she is faithful to me. She has refused going on dates with him.

I asked her to either let this 'friendship' be more public, or to tell him to stop calling. If his intentions are 'friendship' only we can all talk. Am I being too controlling?

Thanks

This seems to be a no brainer. She is involved and exclusive with you. This OM who is a previous lover wants to stay in contact and keeps asking her out. If the roles were reversed she would never put up with this from you. A prior lover who keeps asking your girlfriend out
(and we know what he wants) is simply unacceptable. It is humiliating to you. People who are in exclusive relationships do not allow other people to keep asking them out and because they were prior lovers. I think this is a hugh red flag. She indicated that she seemed in the past to have no willpower against this guy. It sounds like you may be in for a world of hurt down the line. I do not think she is acting in a way a person in a committed relationship should act. If she feels this is controlling then you know her mindset is that she should be allowed to be involved with any and all of her previous lovers. Her attitude will destroy her relationship with you.
I doubt most men would accept this situation very long. She does not sound serious enough toward you. Good luck.

No, you aren't being too controlling at all. It's impossible to maintain a "friendship" with an ex-lover. And besides being impossible, it also shows lack of respect for the betrayed partner. No contact is a must.