Letter to the ex-bestfriend

Dear ex-bestfriend,
Thank you for making me feel as if I was the luckiest person in the world, and that I didn't need anything or anyone else. Thank you for being the only friend I had and thank you for being the only one I could talk to. Thank you for listening to all my crap and telling me I'm more than a wreck and tolerating my tantrums and listening to my stupid rants and picking me up when I fell.
Dear ex-bestfriend, I also want to thank you for leaving and making my entire world crumble down into pieces. Thank you for making me feel alone and worse than I was before. Thank you for breaking all your promises when you said that you're here for me, forever. Thank you for making it so difficult for me to open up to others and to see the world with two eyes instead of four. Thank you for being my best friend and being in my life.
Thank you, I really needed a reality check.
The world isn't all sugar and people will leave and it is going to be so difficult and sometimes you will feel like giving up and thank you, for teaching me this.
You were so important, whether you know it or not.