If you do decide to open up the conversation with your friend, Leeds and Neo both stress the importance of doing so very delicately. For one thing, Neo says, if your friend has already become attached to their partner, getting them to see your POV won’t be easy and could potentially cause a rift in your friendship.
Also, if you believe their partner to be manipulative or otherwise abusive, this person may go the isolation route, planting seeds that friends and family are out to get them—further causing distance between you and your friend. All the more reason to approach things delicately.
“Try to bring it up in a loving and objective way with clear examples. It can also be helpful to remind your friend that only they know what’s best for them and that you will be there no matter who they date,” Leeds explains.
All this to say, opening up a conversation about a friend’s partner will likely be met with some resistance. Show compassion, try to stay calm, and be prepared for a potentially unpleasant reaction.