The dilemma My mother-in-law is rude and offensive. My husband and I have been together over 10 years, and I have coped by biting my tongue and tolerating her attacks because he says if we call her out, she will stop calling, visiting etc. Recently she said something about my family that I couldn’t ignore. My husband asked her to apologise, which she did, but she blamed me for being too sensitive. Now she is, in essence, sulking. My problem is that she sees very little of our children as it is. They adore her, and she adores them, so I don’t want this relationship to suffer. What do I do? I can’t tolerate insults any longer, yet my children deserve a close relationship with their grandmother.

Mariella replies That’s very wise and also sensible of you. You won’t be the first or last daughter-in-law to suffer the sharp end of a mother-in-law’s tongue. That said, it’s all too easy to slip into a siege state with such inherited relationships and display more vulnerability than you would in other situations.

From our beginnings in the playground we all, with varying degrees of success, learn to develop a thick hide. It’s necessary with family, too – sometimes even more so. I’m amused by how many grandparents I see get away with murder as they embrace the power of their returned indispensability in a working world. Instead of patronising them as dusty relics, engaging with grandparents and keeping them sweet(ish) has become essential for the many who rely on them for liberation from the kids. Don’t think they don’t know it! With age comes the boundary-pushing mischievousness of the toddler. I’ve seen plenty of septuagenarians, and older, with a wicked gleam in their eye manipulate an adult child for attention or just for devilment, pushing them to the edge of their tolerance and beyond the limits of their sense of humour.

What is called for is a degree of pragmatism and compromise. There are few insults I wouldn’t put up with for a few guilt-free days of granny-and-child bonding while I absent myself. Left with professionals, my own kids moan, groan and threaten to call ChildLine. A week with their grandparents, on the other hand, and they can’t get their father and me out fast enough. Part of the appeal has to be this return to devil-may-care immaturity that adds spice to life at a time when it would otherwise be losing its zest. Whether it’s plying their charges with sweets, letting them stay up late or tearing up your carefully planned activity timetable the minute you wave them goodbye, grandparents thrive on thwarting your wishes, sniping at your shortcomings and behaving as though the world belongs only to them. I admit to some admiration for this exaggerated and infuriating commitment to pleasing themselves.

Increasingly our parents are filling a void not just when it comes to childcare but also the sort of undistracted focus and fun once delivered by non-working and much younger parents. Manning the childcare chasm and spending quality time not glued to phones and chasing deadlines but watching inappropriate TV shows and scoffing prohibited biscuits, grandparents are the perfect playmates for our children. If biting your lip when the sniping starts is the only cost, I’m tempted to say it’s worth it. Just as we shouldn’t care about insults levelled by strangers on social media, nor should we allow jibes closer to home to hit their mark. Simply because they can provide a saintly service and a rewarding relationship with grandchildren doesn’t mean they themselves are saints.

In fact, bad attitudes or unfettered tongues seem to be one of the liberating qualities of today’s late-lifers, as though the closer they get to the end the more they have to say about what they’re leaving behind. Much of it is less than complimentary. Plenty of our closest relatives are far from the human beings we’d wish them to be (and no doubt vice versa). That’s where a pragmatic and self-serving sensibility comes in. We are not delicate creatures tied to the kitchen sink any more but hard-pressed, active combatants in the big wide world. That means we have to learn to take slights less personally, thicken our skins and do what men have learned over millennia: make pleasing yourself your main priority.

You have a grandmother who can be most useful, so take advantage of all the positive elements she has to offer and turn a blind ear and eye to her insults as you would someone half her size. One day you, too, will have a headful of opinions formed over a long life and a smaller group of people willing, or alive, to listen to them. Put yourself in her shoes, and just remember that “sticks and stones will break my bones but words will never hurt me”. Then hand over some ice-cream money and send them all out so you can have a long, hot, luxurious bath in peace.

If you have a dilemma, send a brief email to mariella.frostrup@observer.co.uk. Follow her on Twitter @mariellaf1