Q. I have an older brother I'm close to, and I've tried to get on with his fiancée, but it's not easy and I usually try to see him on his own. To be honest, he's never had great taste in women. This girlfriend is 10 years younger than him and quite a lot less intelligent. She is very pretty, but seems obsessed with her looks. She also talks non-stop.

My sister admits that she doesn't like her either, though my parents and my younger brother seem totally taken in by her. She and my brother are having a baby, just a few months after my first baby is due, and they seem to expect that we'll now have some special bond and she and I will spend all our time together, as they live a few streets away. We have so little in common and I'm now dreading my maternity leave, but also can't help feeling guilty that I don't like her more. What can I do?

A. I confess to feeling a little torn. I sympathise with you, because there is nothing more guaranteed to make you feel like an evil human being than tail-wagging overtures of friendship from someone with whom you're sure you don't want to be friends.

On the other hand, I'm picturing this poor young woman, gabbling away, desperately trying to fill gaps in the conversation while you and your sister raise your eyes to heaven; wanting you to like her, but knowing that everything she says will be taken down and may be used in evidence against her.

So, first, a few questions for you: just how close are you to your brother, and would any woman be worthy of him in your eyes? Did your sister volunteer that she shares your dislike, or is she telling you what you want to hear? Are your parents "taken in" by her, in the sense that she has manipulated them into approving of her, or do they just have genuine warm feelings towards her?

There are many different kinds of intelligence, as I'm sure you know, and I doubt that the brother you so admire would really throw in his lot with a total bimbo. And while physical vanity seems to suggest a preoccupation with the trivial things in life, very often it is just an expression of a deep-down lack of confidence.

So there you are: the case for the defence. But if you can't like her, then you can't. With babies on the way, though, I don't think this will matter as much as you think. Having babies is incredibly bonding. It's not just the really surprising amount of conversation generated by the minutiae of parenthood. They also throw you into a parallel universe of gusty trips to the park and long, slow visits to shopping centres, which, if you do them on your own, can make you feel as though the world is ending, but with someone else – really, anyone – who's in exactly the same boat, can become quite pleasant. So I'd be surprised if you didn't learn to rub along, even if you wouldn't have chosen her as a friend.

In any case, your brother loves her and you don't have much choice. She's family now.

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