Travelling with someone has advantages: you double your resources, double your wardrobe, have an in-built luggage minder, are assured two shoulders to cry on and have someone to blame when things go wrong.

But be prepared for the concertinaed marriage effect. In a few short months you'll whisk through the dewy blush of the honeymoon; skid into a patch of boredom somewhere near Belgium; be stalled in a permanently foul mood by Austria and be communicating in monosyllabic grunts by the time you reach the Greek Islands. This is all quite normal.

What's isn't normal is when these irritants fester, suppurate and turn psychopathological. That's when you'll find yourself in an on-the-road version of 'Who's Afraid of Virginia Woolf', with you playing a roaring Richard Burton to their screaming sozzled Elizabeth Taylor.

This psychomelodrama, with an internal momentum and logic all its own, will propel you across umpteen different countries, finally self-combusting in a fiery mixture of resentment, anger and too much Guinness in an innocent pub somewhere in Ireland. Avoid this scenario. Get out before the psychotic codependency kicks in.

So maybe you should go solo. After all, there's something romantic about being footloose, fancy free, going where the road takes you.

In truth, though, solo travellers are never really alone – they're more like participants in the travel version of a 70s key-swapping party, randomly attaching themselves to complete strangers with promiscuous camaraderie and then dumping them after a non-committal one-week stand in Prague.

But beware! There are certain keys, belonging to certain types, that should be left in the bowl. But if you decide the road's too lonely without someone, there are some serious do's and don'ts you need to observe.

Do try and negotiate matters such as sex (or the absolute absence of it) and money before you get too far down the road.

It's not as if these rules need to be formalised by names written in blood, but a common understanding is a good starting point.

If things (meaning your travel partner) gets too much, don't resort to homicidal fantasies, try having a day away from each other first. No matter how strong the provocation, do not leave your partner in a blizzard or similar crisis (unless you absolutely have to).

Do not tell your companion you're just going to the bathroom and then nick out the back and take a train to Firenze, leaving them holding the bill in the Roman trattoria.

If you do decide to part ways, divvy up shared items, pay back any outstanding loans and shake hands in a civilised manner, even if you'd prefer to make voo-doo dolls and stick them full of pins.