That Friend often is someone you never expected it to be. A person who simply was there once you needed someone, without you asking him/her to be there. Someone who knew you needed someone.
True Friendship is a Friendship which lasts forever, it's unconditional. It's someone who knows you like no other, who knows WHO you are and respects you for that. Someone who often knows you better than yourself.
When you can say you have such a Friend, you are truly a lucky and rich person.
True Friendship lasts forever.