So, fun fact about depression. You stop talking. The longer you've stopped, the harder it is to start again. Once you've gone so long without reaching out to someone you can't reach out to them again. In your mind they are no longer your friend, you're not welcome in their life anymore. So the silence grows and the distance is greater with every passing year until you can't see them anymore. That's how you wind up alone, drowning in the dark and no matter how many people others can see around you they might as well be ghosts.