The research found 19 per cent of men believe ‘passionately kissing’ someone else other than their partner is acceptable in a relationship.
Conversely only nine per cent of women said their partner kissing someone else would not be a deal breaker.
The Relate and Relationships Scotland survey polled 5,000 people to expose the sordid prevalence of cheating in the UK.
Two thirds of couples surveyed said they would not last if their partner cheated.
But one third of participants reported having been cheated on in the past.
Dubbed ‘The Way We Are Now’, the study has called for better sex education in schools.
Researchers also suggested adults should have freer access to counselling to prevent relationship breakdowns.
Communication was found to be one of the major reasons cheating is considered different to each gender.
Young people aged 16 to 24 were found to be the most concerned about their partner straying.
Almost half (45 per cent) of this age group believed even flirting counted as cheating.
That figure came in substantially higher than the average across the study, which was just 31 per cent.
Researchers have argued overwhelmingly that relationships can survive after cheating.
Relate counsellor Barbara Honey said: “When you can help people to grieve what they feel they have lost and then regain trust and make sense of what has happened, they have a good chance of having a stronger relationship than they had before the affair.
“Counselling is very helpful because it ‘gives permission’ for the processes that need to happen before the pain can reduce and the relationship be restored.
“Often people who have had an affair want to brush it under the carpet and move on, not realising that grieving for the betrayed partner has to happen first.”