Here's a question that can at the same time be incredibly simple, yet incredibly complex. What is a friend? Is it just a generic term that essentially has no more connotations than an acquaintance? Is it something that requires more than that? Do the feelings between two people have to be reciprocal? How much do you have to know about the other person? Their name? Their personality? Their interests? What do you have to do with them to consider them a friend? Merely acknowledge their existence? Speak to them? Do things with them? So many questions, yet few answers. 

Friends will let you down. Friends won't be around. When you need them most, where are your friends? Friends are hard to find. Friends. Yours and mine. I'm taking bout your friends.

You don't have to worry about friends if you don't have any.

How I deal with these kinds of non defined life questions is that you find your own answer to how you feel about these types of things.

A miserable pile of shared secrets.

A miserable pile of secrets.

Whatever you define it to be. In my opinion most people's bar for calling someone a friend is painfully low.

For example I would not call anyone on my Steam friends list a friend. I would say right now only 2 people would fit my standards with a dozen people being friendly acquaintances and another 100 being mutual not-hating relationships.

Where is the problem with that? That means you are in the top 0.0000001% in the world!

Define it as you want to. Regardless, it's a continuous spectrum, and should be treated as such.

what's important is to act logically according to the definition that you have given.

Sometimes your best just isn't good enough. Or maybe you just need to assert yourself a bit better.