Now, I really hope I don't come off as a jerk for saying this, but feeling really bad when your friends are upset with you is normal. I don't know to what extent you're feeling, of course, so it might be depression, but there's also a high chance it isn't.
But anyway, I'm sorry. Friends 2, 3, and 4 have every right to be mad, but more at 1 than at you.