You can lose the plan without losing the purpose.

A plan is one route to a purpose, not the purpose itself, though the two become fused in your mind after you have carried the plan for long enough. When the route fails, it can feel like the whole thing is over, when in fact only a method has closed. The thing you were actually after is still available.

Separate the two on paper. Write down what you were really trying to do underneath the specific plan, in one sentence. Then look for a second route to that same sentence. There is almost always more than one.