We've been friends a long time. You have many great qualities: generous, loyal, always willing to do something for your friends. However, you can also be petty and unforgiving. How many friends have you cut out of your life for seemingly small (to my eyes) things? It's not like you've got a lot of them.
I know that I've been a good friend too. So it's baffling to me that you're giving me the cold shoulder because I was the only person to NOT wish you a Happy Anniversary in the group text. You know, after you clearly went fishing for it by posting a "Happy Anniversary to me and ___!" You do the same attention-seeking thing when you remind everyone that your birthday is coming up. You're not ten years old. At our age, it's needy and sad — it's the same kind of thing your brother does, just on a smaller scale.
Maybe you'll get over your snit soon, but if you don't: eventually, you're not going to have any friends left.