Even now, days after Peter Murrell pleaded guilty to embezzling £400,000 from the SNP where he was chief executive, I am still staggered by his estranged wife Nicola Sturgeon's claim that she was ignorant of his crimes. 

The evidence was there in front of her nose: a £124,550 motorhome, a £3,232 coffee machine, a £3,500 silver wine coaster.

She can't have the foggiest idea what anything costs. If she did, she'd have realised that on Murrell's salary – believed to have been around £100,000 – he didn't have this kind of spare change.

And yet perhaps it shouldn't be so surprising. We all know of wives who haven't a clue about their husbands' misdemeanours – and vice versa.

Critics of Sturgeon blame her lack of curiosity. 

Why didn't she ask about his extravagant expenditure? When she was leader of the SNP, why wasn't she more interested in the accounts? 

Why, when there was clearly something odd in her partner's behaviour, didn't she poke around and get to the bottom of it?

Well, that's a question many a betrayed wife or husband has asked themselves.

Having been completely in the dark about their partner's second families, precarious finances or serial affairs, many people are blindsided when their other half ends a relationship out of the blue.

Indeed, one of this summer's most popular reads is Strangers by Belle Burden, a memoir which examines why her husband simply walked out of their seemingly idyllic married life. Had she not noticed something? Did she have her head in the sand?

In a couple, there is always a choice to be made about how much you wish to know about the other's life.

I don't know many people who scrutinise their partner's bank balances and phone history. Or check they really are where they say they are when travelling on business.

That way madness lies. There is nothing more corrosive than constant, overbearing scrutiny.

Trust is an essential component of a good relationship. It's the discovery that this has been misplaced which is often as hurtful, if not more, than what might have taken place.

Once you've been betrayed – as Sturgeon claims she was by her husband – it's hard not to feel horribly foolish and even harder to imagine you could ever trust again.

The ugly truth about risky solar panels

Our neighbours have been renovating their house and the roof is now covered in black panels. 

Being a bit slow on the uptake, it took me some time to realise these were the much-vaunted solar panels we are all meant to adopt.

They make their home look like the garage for a Batmobile and stand out against all the tiling in our conservation area, but I'd accepted that I should regard them as a 'good thing'. 

Now, after solar panels set fire to the roof of a Northamptonshire new-build last week, and with emergency services apparently receiving a callout every two days for similar fires, I'm starting to slide back towards my previous Nimby attitude.

Gussie was a real flashy tennis player

It must have been utterly infuriating for tennis pro Laura Siegemund to see her opponent Naomi Osaka strut on to the court at the French Open in a long skirt and corset. 

Osaka stole all the oxygen from the opening moments of their match and was then given extra time to change out of it.

But sartorial scene-stealing at tennis championships is by no means a new phenomenon. 

My husband David, who is a repository for ancient trivia, reminded me of American tennis player 'Gorgeous Gussie' Moran, whose outfit caused a sensation at Wimbledon in 1949.

She had a very short dress designed for the occasion by Ted Tinling. 

Concerned about what she should wear underneath – more modest lengths being the norm – she asked the designer to create a pair of lace-trimmed pants, more like fancy lingerie than sportwear.

So shocking was the combination of the short hemline and the lacy knickers, that the courtside photographers lay flat to upskirt her throughout the game. 

More unfortunate still for her opponent, like the flamboyant Osaka last week, Gorgeous Gussie won the match.

My faith in mankind didn't last very long

A few months back I wrote of the heartwarming experience of leaving a guitar out on the street which was claimed by a young man who couldn't believe his luck. Faith in all mankind sort of thing.

Well not so fast. Last week I put a rattan bench outside covered in books I wanted to get rid of. I love the idea of people walking past and picking up a thriller or biography for free.

Above it I wrote: 'Please take books. Not bench.' Guess what? The bench went too, and now I feel a nitwit for thinking it would have been left alone.

Why fans are more fun than the football

I'm not that interested in football, even though I've seen James Graham's play Dear England twice and I'm immersed in the BBC drama, which sadly doesn't work as well as the theatre production.

But seeing fans celebrate is a whole other thing.

Little has given me as much pleasure as repeatedly watching footage of Prince William punching the air and singing Sweet Caroline after his beloved Aston Villa won the Europa League earlier this month.

And the other day there was the elation of the all-too-often disappointed Crystal Palace fans after their team's win in the Europa Conference League in Leipzig, Germany.

It's these moments of joy at the final whistle that I will be hoping for in the forthcoming World Cup. The rest of the tournament, I'll probably be washing my hair.