Worrying news for anyone whose marriage seems a conflict-free zone: a lack of shouting matches doesn't mean all is smooth sailing, it could actually be a sign you're drifting apart.
A three-year study of 40,000 British couples by the Marriage Foundation revealed 80 per cent of couples who split or divorced had reported they were "generally happy" just 12 months earlier. In fact, only 13 per cent of relationships failed because of a period of high conflict or severe unhappiness.
"Abrupt ends to a marriage, violence and arguments are less likely than slowly growing apart," agrees divorce lawyer Marilyn Stowe. "It's a more subtle form of breakdown, where the intimacy ... slowly erodes."
London-based couples counsellor Carole Nyman believes a truly happy marriage is a nebulous concept: "It's normal to have disagreements, arguments, areas of sensitivity - all couples have them. This is life."
Avoiding disagreements is a sure-fire route to developing what Nyman calls "lumpy carpet syndrome" - where issues are not addressed, only to accumulate over time.
Surprising signs you're heading for a divorce:
1. Your spouse stops complaining
Nyman says "resentment is a number one killer of desire, in both genders". If you're married to a tortoise-type who would rather take shelter under their shell than argue their point, the unsuspecting partner may think that the issue has gone away.
2. You both put your kids first
Work and children can place pressure on relationships and they inevitably have to come first, at times. But Stowe says that consistently channelling all your energies into your children, instead of each other, can backfire in the long-term.
3. You're more interested in other relationships than your own
Making comparisons with other couples is a tell-tale sign your own relationship might be suffering.
4. Your friendships suddenly become more important
Not looking forward to an end-of-day debrief with your other half suggests your lines of communication are breaking down. This can result in finding others to confide in.
5. You don't wonder what the other is thinking
Stowe says warning bells should ring if "it doesn't particularly matter to you what your spouse thinks".If it feels irrelevant or pointless to talk to your spouse then "[emotionally] you are shutting the other off."
6. Your sex drives are out of sync
Both Stowe and Nyman think changes to your sex routine are one of the first signs something is not right. If either or both of you regularly start feeling rejected, it can easily lead to a rift.