My girlfriend and I have been together for eight months. We love each other dearly. But she will go to university in Edinburgh and me in Leeds. What proportion of couples survive living apart in such sociable environments? Are we less inclined to be faithful because we are lesbians now and were initially straight?

Separation does not make the heart grow fonder. It makes you row when you reunite and say goodbye. Expert Dr Gregory Guldner, who runs the Center for the Study of Long Distance Relationships in southern California, says long-distance relationships are no more likely to split up than geographically close ones. This includes long-distance relationships among university students (he estimates up to 80% have one at some time). A study from Flinders University, Adelaide of 18 people in long-distance relationships because of work showed they felt emotionally close, more so if they shared the mundane things that happened to them.

Staying faithful depends on how committed you are and your attitudes to being unfaithful. It also depends on how easy you think it would be to find someone better and the cost of doing so - ie, how solid your relationship is. Bear in mind that most relationships at your age don't survive - and most relationships don't survive: the Office for National Statistics says that, on average, people who live together don't make it past four years and more than one-third of marriages end in divorce.

A survey of 200 people in long-distance relationships by Guldner showed that most expected to live together within four years. So if you're not thinking long term, then maybe it's worth splitting up to avoid future pain.

There is a lot of research comparing 'same-sex' and 'cross-sex' couples, as psychologists call them. There is no evidence that lesbians are more likely to be unfaithful - rather, they place more emphasis on openness and making plans as being indicative of commitment. So sexuality or geography won't determine your fidelity - it'll be the same things as for everyone else.

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