Time is invested not wasted

You did not waste your time.

You spent time.

You spent it because there was a price, it costs you something.

Understand that you came out of it with something of value. 

Not a wasted moment.

You paid for this experience with something as valuable as your time, therefore something was gained. 

It will help you develop into the more of you that needs to be brought forth.

Step out of this knowing that you've invested in yourself.

So all time invested, no matter your point of view, is time well spent.