A little fact about me:
I over plan. I do. I like planning okay, I can't help it. But...I am aware that most of my friends are not like me in this regard. They just like being a little more flexible and/or spontaneous. I get that. But if I ask you to do something with me, like going shopping for bathing suits or even just going to eat at a place that is 5 minutes from your house, and you agree...but then you pretend like I never asked and I don't hear from you for 5 days just because you don't like to plan things out at all...then that's going to piss me off.
I'm not the greatest friend in the world, I'll admit. But damn it, I try and put effort into my friendships. I just want to same courtesy.