15 ways to bulletproof your relationship

1 One of you is ready to kiss and make up

Are you always the first to apologise after an argument? A study earlier this year found if one of you bounces back quickly after a row, moves on and avoids sulking, your marriage is likely to be stronger and happier. Interestingly, you don’t both have to behave like this to reap the benefit – so if your partner's the mature sensible one, a little sulking can’t hurt!

2 You spend more time in the real world than the virtual one

According to lawyers, Facebook has a lot to answer for. 'We deal with 5,000 divorce petitions a year,' says Amanda McAlister from solicitors Russell Jones & Walker. 'Facebook and Friends Reunited are cited as grounds in one-third of cases. Social networking sites can be addictive, and sometimes it's hard to resist a first love who gets in touch after 30 years.' Experience has taught her honesty is the best policy: 'Be upfront about who you're in touch with online – many of my clients hit trouble when they start keeping secrets.

3 Both of you give your brains a workout

It's said only fools fall in love, but intelligent people are better at staying in love. A US study found those of below-average intelligence are 50% more likely to divorce than those with a higher IQ. So exercising your brain – whether it's Sudoku, evening classes or conversation – boosts more than just brainpower.

4 Stand up for your individual rights

There was much talk a few years ago about the Surrendered Wife movement, in which women just did exactly what their husbands said in order to make them happy. But a recent survey found that women who see themselves as feminists are more likely to have stronger relationships and enjoy a better sex life.

5 You still laugh at his silly jokes

That's a good sign. 'Laughter lowers our levels of stress hormones, which impacts on how irritable we feel,' says Trudy Hill of introduction agency Seventy Thirty. 'Stress can turn off your sex drive and make you put up a barrier. So rent a film that cracks you both up – you'll feel refreshed and happier.'

6 You’ve given up smoking

The more similar people are in values and habits, the more likely they are to have a successful marriage. If one half of the partnership is a smoker, you’re 75-91% more likely to split up than couples of same-smoking status. Quit, and you'll live longer – and spend more years together.

7 The power of yes, yes, yes! (It’s not what you think…)

How often do you say yes – or another positive phrase – to your husband? Psychologist John Gottman says he can predict whether a marriage will end in divorce by listening to just a few conversations and counting how many positive things are said compared to negative ones. If you say five nice things for every snippy or downbeat comment, the marriage is likely to stay strong.

8 There’s a nice, soft sofa in your living room

You may not think furniture could affect your marriage, but research from Harvard, MIT and Yale Universities say the hardness, weight, shape and texture of certain furniture may have an impact on your mood: 'If your surroundings are calm, you’re likely to be calmer,' says behavioural psychologist Jo Hemmings. The perfect excuse to redecorate…

9 You 've got a good work/life balance

There are some careers, such as nursing and teaching, where divorce rates are very high. 'Those in the caring professions often find it hard to switch off at the end of the day, and may be psychologically exhausted,' says Hemmings. 'Rather than changing careers, aim for a balance between communicating with your partner and burdening him, so you both can switch off when you’re at home.'

10 You finish each other’s…sentences

Shared speech patterns show you’re on the same wavelength. Psychologists found that compatible couples use similar phrases or synchronise their speech without even noticing. You can analyse your own text message conversations at Utpsyc.

11 You grinned in your old school photographs

We may cringe when we look back at those pictures from our student days, but a study in Indiana looked at the high school photos of 650 adults and discovered that those with the weakest smiles were three times more likely to divorce later in life. Researchers believed those who are generally happier are more likely to work through difficulties in marriages and relationships – bad news for those of us who went through a moody phase in our teens!

12 You always get a good night's sleep…

A bad night's sleep can ruin your day, but more than a few of them can also ruin your relationships, according to psychologists. 'There seems to be a vicious cycle,' says Brant Hasler, who carried out the research. 'Sleep affects the next day’s relationship functioning, and the relationship functioning in turn affects the next night's sleep.'

13 …and remember that the bedroom isn't just for sleeping

We're not saying you should swing from the chandeliers five nights a week, but researchers at the University of Tennessee recently confirmed what we already suspected: regular sex counteracts the 'happiness deficit' that sometimes creeps into a marriage as the years go by, and makes couples more content. 'Keep it spontaneous,' says Hemmings. 'There’s no use doing it every Sunday at 10am on the dot – it'll get predictable. Find the level that’s right for you.'

14 Never having to say: 'Could you do the washing up?'

'I’ve taken the bin out' or 'I’ve done the dishes' could be the most romantic words ever said. According to a recent survey, sharing household chores ranks third (behind fidelity and a good sex life) on a list of what makes a relationship work. 'If one person is doing the lion’s share of housework, they end up feeling undervalued,' says Relate counsellor Paula Hall. 'But don’t let this spill into rows – explain to your partner how you feel, rather than getting into a discussion over who does what.'

15 You’re grateful

Happiness comes down to three little words: 'Thank you for'. Couples do little things for each other all the time, and simply expressing gratitude produces a little happiness boost that can last for days. 'Couples often stop bothering to do this as the years go by,' says Hemmings. 'But if you get praise for something, you feel happy and want to do it again. It creates a kind of cycle of contentment.'