As a 29 year old female I've suffered from depression and anxiety since my early teen years.
My personal experience is, I had been depressed and in a dark place. Felt alone. Misunderstood and ignored and unwanted because I felt like I was not important or a waste of time and space to the world in general and sometimes still do.
I do agree in a sense when you, the sufferer are being selfish. We have to be the one to make the choice to be positive and get help. If not then it can be selfish when you consider the facts.
Me not being in this world would negatively affect not only me but my family because they need me, love me and want me aroand. I would cause them grief and sadness. And I the sufferer of depression am being selfish in not considering their feelings when faced with this stare of mind and mental illness of mine.
I have attempted suicide and still think about it. But I habe positive reasons to bring me back out of that dark place.
So in a sense yea it is selfish but I would never openly say it to someone. I would rather remind them the wonderful things the world holds for them if they stick around and battle through life.
Not only the experience will make you a stronger individual but it will help you find yourself if u stick to it and keep trying to seek help keep your chin up. And yes this is no easy feat for people with depression it's a large mountain to climb or seemingly impossible.