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As Tess Daly puts on a brave face during another alleged sex text scandal involving husband Vernon Kay, public opinion divides between those who admire her for 'standing by her man' and those who think she should dump the b*****d quick smart.
Is forgiving a cheating partner a sign of weakness or strength?
After all, both leaving someone you love and staying with someone you love who has hurt you are both difficult.
How soon into the relationship it happens is also highly relevant. The earlier the infidelity, the less chance the couple have of making it.
Giving them another chance feels like the right thing to do.
Do you deserve better? Do your kids deserve better?
If your honest answer is, 'My partner is worthy of us, he/she just made a horrible mistake' your loyalty is probably deserved.
You can understand how and why it happened
Was the relationship going through a rough patch? Was your partner struggling with something like the death of a parent or another traumatic event?
If you were put in their situation, would you perhaps have done the same thing under the same circumstances?
I'm not suggesting cheating is ever justified - it isn't - but it does help if you can at least understand how it happened and their explanation of why rings true?
You suspected something wasn't quite right
You're far more likely to forgive an affair if you were suspicious and your instincts told you something was going on.
The more confident you are that you would spot the signs if it happened again, the more likely you are to trust again.
This behaviour is uncharacteristic
If up until now (and in other areas of their life) they are trustworthy and reliable, it's a good sign.
If you still think they're a nice person and have your best interest at heart, giving it another chance is sensible.
Your friends and family think staying is the right thing to do
If your partner is well liked and people who know both of you are shocked by what's happened and supportive in your decision to work through it, it's a very good sign you've made the right choice stay.
They are clearly sorry about what they've done and feeling just as bad as you are about it all
They need to be obviously remorseful and prepared to do pretty much anything to make it up to you.
It's the best thing for the children
Just make sure it is.
Staying together 'no matter what' for the kids isn't always the best solution.
Growing up with parents who are locked in a toxic, destructive relationship is not a pleasant environment in which to start life.
Children are sponges: they watch and see far more than you realise and their future relationships are strongly influenced by how they see their parents relating.
Having two happy parents who live separately is preferable to two parents who live together but clearly can't stand each other.
They're willing to get counselling
I'd strongly recommend any couple battling the aftermath of a messy, soul-destroying infidelity (and aren't they all?) to visit a therapist together, even if it's just for a few sessions.
Being able to battle it out in a safe environment with someone unbiased who can guide you through it, is critical to how quickly and how well you get through this.
If your partner refuses to even consider the idea, it's often because they're worried they'll slip up about other infidelities you don't know about.
Or they simply don't care if you stay together or split.
Staying together 'no matter what' for the kids isn't always the best solution
You're strong enough to fend off the criticism
Lots of people who will think your decision to stay condones cheating and sends a bad example to others.
It's totally dependent on your individual situation but, even so, be prepared to either defend yourself or make it clear it's no-one else's business.
You're convinced it's over or won't happen again
This seems obvious but you'd be surprised at the amount of people who give their partner another chance without really knowing they've stopped contact with the person they cheated with.
Or continue to let them associate with the same friends or colleagues who led them by the hand into the path of temptation and encouraged it.
It hurts but you're confident you can eventually move past it
Do you secretly think forgiving them means 'they've got away with it'?
If you intend to make them pay for what they've done every single day you're together, what is the point?
You're willing to learn from it
Therapists say one of the best questions to ask afterward is 'What did you like about yourself during the affair?'
An affair holds up a vanity mirror, the kind with all the little bulbs around it. It gives you a rosy glow to the way you see yourself.
A marriage or long-term relationship is more like a make-up mirror that magnifies every little flaw.
Relationships do survive infidelity - especially if it acts as a wake up call and forces you to address long-standing issues you've both been ignoring.
IT'S UTTER MADNESS IF:
Pretty much every partner you've had, has cheated on you
If all your partners cheat, you need therapy not yet another partner who treats you badly.
One partner cheating is a mistake, choosing partners who are always unfaithful is a relationship pattern that means (at best) you have low self-esteem or (at worst) are battling more serious issues.
Get help (itsgoodtotalk.org.uk or relate.org.uk)
They have a history of cheating with other partners
If they've cheated on every person they've been out with - and nothing's changed in their life to make them rethink their behaviour, it's pretty much guaranteed they'll do the same to you.
This isn't the first time they've cheated on you
Spur-of-the-moment no-strings-sex may represent nothing more than opportunism, fuelled by one too many drinks.
But it still breaks the trust bond and, if discovered, has the power to destroy a 20-year relationship in one second flat.
Infidelity is incredibly painful to recover from.
If you have forgiven your partner before and endured the long, painful process of learning to trust them again, them cheating a second (third, fourth) time sends a clear signal: your feelings aren't that important to me.
It doesn't necessarily mean they don't love you if they cheat but it does mean they don't respect you and have a different value system.
They refuse to admit to an infidelity when there's irrefutable proof
An unsupported accusation may well be just that: rumours or suspicion.
But if you have solid proof your partner cheated and they're still lying to you, why would you believe anything else they say?
They don't have a good reason for doing it
You were getting on well, everything was fine in their life and they can't even come up with a plausible reason other than 'It just happened' or 'I was drunk'?
You're staying? Really?
They lie about other things as well - and are convincing
Honesty is the basis of most good relationships and being lied to is often what people find the hardest to come to grips with after an infidelity.
'I can understand she wanted novelty sexually and have made peace with that, ' said one man whose wife had a three-month-affair.
'But I can't forgive that she blatantly and consistently lied to my face about where she was and who she was with. She was so believable, how can I ever trust her again?'
If you honestly don't think you'd know if your partner did it to you again, why would you stay?
You struggle with trust issues or jealousy
Everyone struggles after finding out someone they trusted has done the dirty on them.
But if you are prone to jealousy or have real issues trusting (you've been burned before, parents had an affair) it's going to be doubly difficult for you and it's unlikely the trust bond can be repaired.
Absolutely no-one supports your decision to give them another chance.
If there's even a tiny amount of logic to you forgiving, you'd have at least one person on your side.
See reason - walk.