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.
God speed bro.
As far as feeling like you've wasted time, I think everyone gets that to a degree. But don't dwell on it, just move on. Find a hobby, volunteer group, religious things or something to help your life feel more full.
Friends and relatives get married, and you might have less time with them, but hopefully they still do the things they enjoyed doing with you. Their marriage shouldn't end your friendship. But I reference back to finding something to do with your time and you will likely meet new friends as well.