Real friend?

I always believe being diving into relationships we have to deal with friendship. Or perhaps the "procedure" is: family --> friends --> relationship. I am kind of stuck in the middle right now so no doubt relationships aren't going well.

Recently it got me thinking what a best friend needs to be. Always be there to support? To listen? To help? Perhaps that's the basics.

But it got me thinking - some "friends" aren't really being a "friend". There are perhaps one or two friends whom I can trust and talk to and tell everyone to them, and of course they tell me everything too and yes they have been a great support to me.

Some others.... well I treat them as a best friend too. I tell them everything. But what I got? I got teased at based on all those "secrets" and at times being threatened they would leak them out too. And, on the contrary, they never tell me about their lives. Not that there is nothing to tell, but every time I had to find them out myself via various sources and sometimes have to guess the meaning between the lines, then put two and two together and know what actually happened.

Oh well I guess the best is the avoid these people that aren't really best friends... and that is what I am trying to.