That is all you have to do. It does no good whatsoever to blame or beat your self up. It only makes you feel like a failure. It is more important to save than be perfect. Secondly, wise partners actually plan for failure.
All new strategies are prone to fail somewhere along the line for rather benign reasons.
Instead of blaming each other for a failure, why not simply try to identify where and how the plan went wrong. Building in ways of remembering, planning for emergencies when they come up or reevaluating the entire plan are much more important than pointing a finger at who fouled up. By doing so you will demonstrate your commitment to each other instead of turning things into a war of blame which no one will win. One really easy way to help you save is to set up an automatic investment that is taken out of your bank account every month. This way, you won't have to think about it, worry about it, or fight about it.