I am so guilty of not getting back to people in a timely fashion.
Do you ever get a message from a friend/relative and think "Ha! YES! I have blahblahblah...." and don't actually respond and then that lack of response makes you feel all terrible so you avoid and then it comes to a point where you've avoided responding for so long that you can't respond and then you finally respond with a billion apologies trying to explain and you know the other person doesn't believe you?
That's me. With everything.