Too Lazy; Doesn’t Read (TL;DR)

Originally this phrase was Too Long Didn’t Read or TL;DR. This expression was first used on me by someone I considered a friend. After looking up the new acronym, I was insulted and a little hurt. Well, not immediately. I knew that they were busy with school and had family issues that took up a lot of their time and mental capacity. Then it occurred to me that if in fact they were too busy or too tired, why did they take the time to even be where they could see what I wrote? After all, it is not as though I wrote it out in soup in the kitchen floor. So, they must have had another reason for taking the time to write those four letters. What could those reasons be?