I am a big Judith Martin (a/k/a Ms. Manners) fan. My wife passed along to me Ms. Manners’ typically insightful piece of advice to one family’s problem:

Dear Miss Manners:
What should we “loving family members” do after our “beloved family member”:

1. Marries, has three children, divorces a man;
2. Asks us, “Why didn’t you tell me you thought he was a creep?”
3. Has a long-distance lover for four years (not during marriage) — whom we all really like — but who never seems quite able to move to her city even after three job and city changes — due to career opportunities — and has canceled vacations with her (and us) at the last minute;
4. Flies to see her lover every other weekend because it’s “easier” for her than for him;
5. Cries to family members about her finances, how hard it all is for her, and about her ex-husband not letting her move with the children to her lover’s city;
6. Becomes very resentful when we family members finally tell her that maybe her lover isn’t playing fair with her?

Were we wrong in addressing our fears to her? I now fear for our future relationship with HER.
Ms. Manners: You must realize that you were wrong to think it would help. Much as Miss Manners sympathizes with the desire to shout warnings when observing someone pursuing disaster, she recognizes that there is a time to give up.
The answer to your relative’s accusation that you failed to warn her should be the formula you use when tempted to issue futile advice: “We were (or are) relying on your judgment.”
The hope is that this will eventually make her realize that she doesn’t have any, but Miss Manners is afraid that it might be a long wait.