Infidelity and family law: what to do if your partner is cheating

17 October 2023

Shocked, betrayed, confused, and angry are some of the emotions you are likely feeling if you have discovered your partner is cheating. Finding out your spouse or partner is having an affair can be devastating. The dissolution of a marriage or the breakdown of a long-term relationship is incredibly upsetting marked by the loss and shattering of a future together.


Discovering an affair places a huge strain on a relationship. It can take people years to overcome the impact of infidelity. Treading carefully in the early days of discovering an affair is crucial to protect your wellbeing and give you space to consider your next steps so they benefit you rather than acting in retaliation which you may regret later.


Should you stay or should you go?

There is no right or wrong response to a partner’s infidelity; whether your aim is to salvage the relationship, or you've decided it's time to move on, there is work to be done – rebuilding the relationship or contacting a family lawyer for legal advice.


Counselling can be effective in supporting couples to restore the relationship. However, if you decide to officially end the relationship (either through dissolution or an agreed separation agreement), as well as the heartache, there are legal, financial, parental and practical challenges to navigate. Both scenarios require open dialogue.


Why seek legal advice after your partner has cheated?


  • Expertise and experience: family lawyers specialise in navigating complex family law matters, including those involving infidelity. Their experience and knowledge means you receive accurate and up-to-date information.
  • Objective guidance: emotions often run high during family law disputes related to infidelity. Family lawyers provide objective guidance, helping you make informed decisions without being clouded by emotional distress.
  • Understand and protect your rights: family law advice ensures your rights and interests, as well as those of your children, are protected. Whether it's property division, child custody problems or financial arrangements, a family lawyer advocates for your best interests.
  • Legal process: family law proceedings involve legal procedures and paperwork. A family Property division: a family lawyer determines which assets are considered relationship property and which are separate property, ensuring a fair division.
  • Negotiation and mediation: an experienced family lawyer assists in negotiation and mediation efforts to reach a resolution that considers the impact of infidelity on both parties.



Two fingers with faces drawn on them are holding a wedding ring.

How does cheating affect dissolution in New Zealand?

There is a misconception that if a partner cheats, the outcome of the divorce or separation is affected with respect to financial settlement and childcare arrangements. The reality is that this hurtful behaviour does not have any impact on the equal sharing under the Property Relationships Act (if you have been together more than 3 years).


However, if you are going to be forced into an economic disadvantage, the court may decide you should get more than half of the relationship property. It can be complex to negotiate so seeking legal advice our Relationship Property lawyer Christchurch team is essential to secure the best outcome.


It should be noted too that New Zealand’s no-fault divorce means details of the infidelity do not need to be included on an application. By removing the requirement to assign blame, there is typically less conflict, and it encourages more amicable divorces. As family lawyers Christchurch’s Weston Ward and Lascelles have a strong focus on non-confrontational dispute resolution, our goal is always to get the best equitable outcome for our clients and their dependents through the least stressful means.


If you have any questions or require further information about how we can help you, contact Weston Ward and Lascelles’ Christchurch family lawyers. Our friendly team offer discreet and confidential advice, and work tirelessly to support our clients in their time of need. Call 03 379 1740 to make an appointment.

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