Depression Support Group
Depression is a real and debilitating condition that is often misunderstood by family and friends. Its meaning can range from a prolonged period of sadness to an actual mental illness with specific symptoms. Find and share experiences with others who are going through the same struggles.
You made a mistake. It is what it is. All you can do is apologize and express how awkward you feel. Remind them that it is temporarily misplaced and that you hope it will turn up. In the meantime, they may have to replace your key.
We've all done it (lost a key, pager, other). Just try not to be so down on yourself.