LRavenscroft - like several others on this thread, I 'know' this lady - she is a member of our book group where we don't restrict ourselves to discussing the book. She's a kind, generous, and friendly person, but has obsessions about a certain family member and introduces them at every opportunity, proceeding to try to monopolise the conversation about that person. Privately the rest of us have discussed how to manage her and now we all make the effort to curtail her conversation when it becomes domineering. Likewise if she tries to start a 'private' conversation with the person next to her, that person responds by saying something like "Oh I'm interested in this other discussion, I'll talk to you later". These approaches are helping in a subtle way. If, however, you want to be more direct, you could be honest with your 'good friend' and suggest that you introduce a rule that in any chat, when anyone is holding the floor, they may only speak for 3 mins, anything more becomes a lecture - tell your friend that none of you wants to be lectured, and that if she really 'adores' the other person, she should fall in line with you in order to protect the domineering lady from being excluded from other groups. This may be the only group of friends she has managed to retain, courtesy of your good friend.