My grandfather had awful sayings to illustrate truths. One was: you can't ride two horses with the one arse. This applies to everything from deepest relationships to what you're going to have for dinner.

For some years I've been witness to three women waiting on men to leave other women who they claim to no longer love. Two are older and one is in her early 30s. They had decided to remain faithful to a prospect rather than a present. Lately, two of the women decided not to wait anymore.

The men who had it both ways for so long are suffering. Both had women they lived with in name only. The women they claimed to love more, but did not live with, are good, loyal, intelligent and truthful. Their love for a man who was not available caused them concern and pain. They have been judged and damned for being mistresses, but they had not taken the role willingly. They were part of the three-pointed dilemma that has dogged lovers since love was invented.

My older friend decided that since her husband's children had both left home the excuses for him not doing so had run out. His wife has her own life and has had for 30 years. My friend has her own income and had no desire to undermine her lover's insistence that he support the family he created. In fact, she admired it. There were no claws in this woman's approach. She just wanted him to commit to what he says he feels.

He waited too long and she has gone through a terrible time withdrawing from him. They haven't seen one another in two years and he still writes. It's a Hepburn/Tracy conundrum. The two stars of screen were madly in love but he wouldn't divorce his wife and she wouldn't allow him to. She took five years out of her career to nurse him before his death.

Nothing so noble and lofty for the younger woman. Her boyfriend went between herself and another woman for too many years and neglected the daughter he had with her in doing so.

Her move to Spain last summer made him realise she was the woman he wanted to be with. At the time I thought it was largely to do with the fact he was going to walk into her new business and get a job and have a Mediterranean lifestyle. The other woman back on Irish soil wasn't offering half as much variety and interest, so she got dumped and he followed my friend to the sun. He was there two months before she realised that having him around all the time was stressful and no good for their daughter either, since he had no tolerance for children.

She told him that it wasn't right and tried to be reasonable about access to their daughter, a thing he was lax on when they were both living in the same country. The heel said he didn't want to see her if he couldn't have her mother. He went straight back to his other woman, who told him he could stay out of her life too. His comeuppance took years off my friend. Her last words to him were: "We're not a two-for-one offer and we never were."

- Suzanne Power