‘ I would never be unfaithful to my wife for the simple reason that I love my house too much.’

Bob Monkhouse

Infidelity is like a hand grenade with the pin already taken out; you don’t know when it will blow, there’s a febrile excitement in the meantime, but blow you know it will.

If you are determined to be unfaithful, then be a kind infidel, and try to be faithless without causing hurt (beyond your own eventual heartache), which means don’t get caught. Be prepared to live like a spy, leading a double life, packed with credible lies and at the end of it, as end it will, be prepared to disguise any heartache and re-embrace your former life. Don’t use close friends as alibis, or place them in compromising positions. It is quite unforgivable to test their loyalty in this way.

If you suspect a friend of having an affair – or if they have confided in you – restrain any impulse to interfere, or reveal all to the wronged partner. You dabble in the delicate architecture of a marriage at your peril, and may well find yourself blamed in years to come for wanton destruction.

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