This isn't a letter because I would never write him a letter. I do fear a variant of this conversation may one day be had. I hope not. I'm not even sure I would have the heart or the guts to tell A all of this in real life. But it's a good illustration of how Ns work.
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A: I've noticed you don't really do anything much for your mother. I do so many things for her. Willingly because she is such a lovely person. So's your father. But you're her daughter and you seem to ignore her most of the time.
Me: There's a reason for that, A. But I don't think it would benefit you or her for you to know why. How about you just take her as you find her and enjoy your relationship?
A: Because I think you are really unfair and horrible and I want you to justify it. She's a lovely friend, so kind and caring. And such fun to be with. You don't even come to her parties and I know she's sad about that. Surely you could attend a party even if you don't want to do any of the running around that I do.
Me: I don't owe you any explanation.
A: Maybe not, but I'm doing so many things that a daughter could and should be doing. I want to know why you're not, when she's your mother and loves you so much.
Me: OK. But before I start on my reasons I'm going to address your friendship. You're basing your view of what I should do on what you believe her to be like. I expect you're not aware of how she likes to gossip behind your back. She's told me all sorts of things about you. She totally disapproves of you being gay, by the way. You should hear the vile things she says about gay men. And she's been encouraging the affair R (A's husband) has been having with MG (a neighbour).
She first got the information from MG who was boasting about it to her. And she told him she wasn't surprised, because you've confided in her about your low sex drive. You told her you would rather think about cheese than sex. She is very keen for your marriage with R to end. Because then you won't have to run around after R at all. You can spend all your time looking after her instead. So she's been telling MG he shouldn't feel guilty. That MG is doing you a favour by having the affair with R. R is, after all, a hot-blooded young man, she says, and it's quite understandable he has physical needs. And she's been telling MG about all your health issues causing your lack of libido. Oh, and telling me too, obviously. You were telling her in confidence were you? Oh well.
She's also been encouraging MG to arrange those group holidays you hate. She's pointed out to MG that a group holiday would give him and R lots of opportunities to slip away for assignations. And she's going to encourage you to go on the holidays, even though you hate them and you have to pay for them, because she'll remind you that R is always wanting holidays. And she'll advise you that you should go on these holidays with R or he might get unhappy and leave you. Especially since you're so woeful in the bedroom. You'll think she's giving you advice to keep your marriage intact. She thinks there's a good chance of you uncovering the affair on one of these holidays and then you'll get rid of R. Job done.
So, now we've got that out of the way, shall I move on to what she's done to me along the way? Where are you going? I've got plenty to tell you. You did ask...OK. Bye, then...