S usanna Abse has been a marriage counsellor for 30 years and gives her peerless insights into the challenges couples face. I think you'd feel comfortable saying anything in front of her, unless it was bullshit. You want to take your A-game, but you trust her with your marriage.

Abse can't estimate how many couples she's seen since 1986, but she can say that it's been tens of thousands of hours. She has worked with every kind of couple, from the ones who bang their heads together and shout and stand up and walk out.

She sees a few weekly or biweekly. She says a couple will continue to meet with her for as long as it takes.

There has been a rise in the number of couples seeking therapy, but it is not as dramatic as you might think. If the field is booming, it's because younger couples are seeking help earlier in their relationship, at a point when older generations would have just called it quits. The rise probably isn't hurt by the popularity of shows such as the BBC's Couples Therapy, which sheds a light on this usually hidden process.

couple in bed

Anxiety builds around sex, and with it the ability to communicate. Photograph: William Elliot/William Elliot / Gallery Stock

She says that when she started practicing, there used to be a rule that you never asked a question. They are always related to a missing relationship with someone.

The theory that you could predict which couples would fall apart from four red flags was published in 1983 by the celebrated American psychologist John Gottman. Abse says lots of couples will be contemptuous at moments, or stonewall at moments. Isn't it a defence? Or a response. My job is to find out what the meaning of it is for the couple, and for them as individuals, in relation to their own childhood experience.

Abse does not do rules. This is a list of eight essential truths for a happy relationship.

Be aware that having children will change your relationship in a way that you can’t prevent

It’s good to fight

Abse says that if a couple never argue, it is because things have been parked. In her book, Tell Me the Truth About Love, Abse describes two people who have avoided conflict with each other and turned their anger towards each other. Children of avoidant couples can becomerepository for trouble. The couple are nice. They have a child who is doing drugs and acting out. The child will be projected all the difficulties between them.

Stop blaming

Abse says that he makes a joke about listening carefully to all the submissions and pronouncing it correctly. I will judge them based on the fact that one has done something heinous and is in the doghouse, and the other is not. It is not like that. You cooked this up together.

She says that one person wants to get closer to the other person, and they might think a therapist can tell them who is in that situation. There is no right or wrong because they have created this situation together. A distance regulation system is what family therapy used to call it. Even if only one person complains about it, there is still an unconscious conspiracy to keep the distance between them.

Use ‘I feel … ’ rather than ‘You always … ’

The old saw is that you should use words rather than accusations. You make yourself very vulnerable when you describe your feelings, particularly if they are fearful or sad. It is not safe to show people how fragile you are. It's difficult for you.

Don’t have children (well, do if you must)

One message that comes across in so many relationships is that what drew the couple together in the first place was not a shared love of hiking or a similar education, but the dynamics of their childhood.

Those expectations that you're going to meet a loving, parental figure that you want in your childhood are impossible when you throw children into the equation. There isn't a lot left for mothering and parenting there. It becomes a conflict of needs.

After children, relationship satisfaction crashes. Many couples grow and mature through having children. It's possible that the rule is to be aware that it will change your relationship in a way that you can't prevent, and that you can't get ahead of how that change will make you feel.

Have sex (or don’t, but at least notice when you stop)

Abse says that there are a lot of nonsexual couples. If you are in your 20s, 30s, 40s, and probably up to your 50s, there is a risk that you will end the relationship if you don't have sex. People want the release, they want the intimacy, it's an important part of life.

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If your sex life flags, don't assume it will go away; anxiety builds around it, and you can't communicate. Probably not.

Threats of leaving are a bad idea

Abse says that they are corrosive and undermine a sense of security.

Don’t label each other

I used to think that everyone thought their parents had personality disorders. Everyone thinks their spouse has a disorder.

You have to label children in order to get resources. Abse doesn't think it's helpful with adults. You have to figure it out. It's crazy to say that adults with attention deficit disorder are related to it. It's just called anxiety.

Be brave

Couples come and think, we are in couples therapy. It's all over. They want you to be nice, they want you to be nice. They want to feel safe. It's a scary thing and the fear is that the end is separation. The process of seriously examining any relationship is often about psychic separation, because they are caught up in a dynamic in which they are confused. They are projecting on each other, they are confused about who is who. It always involves looking at someone again. It is a question of whether it is a real separation.

Abse's book is dedicated to her husband. She says it is true and that is what is going on. He thinks he has the truth, and I know I have.

Tell Me the Truth About Love: 13 Tales from the Therapist is a book by Susanna Abse. Falling and staying in love is an interactive workshop with Susanna Abse that will be held on 15 June.