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.
Since you will have to be late you won't have to stay very long.
Maybe just a quick drink and a snack, staying close to the [people you like and just be cordial to the rest of them.
Then develop a very early appointment and skedaddle.
The other thing to consider would going to the party be a minor annoyance or would it send you into a total tailspin?