I'm the same, despite being guilty of writing long posts too. Sometimes I love a long, detailed, interesting post. Sometimes I see a long post and just skip it. Sometimes I just close the tab of a thread because the first post it too long and I'm having trouble following it.
I do like the way some people do it with a "tl;dr" version. For those who don't know, it stands for "too long, didn't read", and originally it was a criticism people made. Then people started adding a "tl;dr" part at the bottom of their posts, a one or two sentence summary, bold so people could find it easily. And sometimes, now, the summary is added to the beginning of the post, and I like that best. After reading the summary, it's usually much easier to follow the long post, and you don't run the risk of spending a lot of time powering through a post that ends up not really telling you anything you cared about.
I'll try to remember to use that more often myself.