If you were to split up with your partner then your joint life insurance policy can’t be divided.
In that situation, you’ll probably need to cancel the existing policy and set up two new ones. As you’ll be applying for a new policy at a later stage in your life, this could result in a higher premium. However, it will also give you each the chance to review your needs to see if a new policy would better reflect your changed circumstances - for example, if you have a smaller mortgage or reduced expenses.