With any big life change it is always recommended that you review your Wills and succession plans – including if you get a divorce.
A divorce doesn’t necessarily invalidate an entire Will. But if you have named your ex as your executor, for example, then this will no longer be valid. That's because if you divorce, upon your death, your former spouse or civil partner is treated as having predeceased you.
If you still wish your ex to inherit your estate under your Will then you must update your Will to this effect. This is unusual but not uncommon, especially where a couple share young children.
It is always advisable to review your Wills after a major life change such as divorce, to ensure that they remain in accordance with your wishes and take into account any change in your circumstances.