“I need to include at least one picture with every blog post, for SEO, Google+, and Pinterest.” If you don’t write anything, there’s nothing for a search engine to fine and nothing to be shared on Google+ or pinned.
“I need to finish that major project on the blog before I write any new posts.” The project isn’t as massive as you’re making it out to be in your head and you did the most urgent portion of it in 10 minutes just now.
“I’m too busy training for the Tour de Cure, working, and doing homework for my class – I don’t have time to write a post.” Stop making up rules about what a blog post “should” be – you can write a sentence and be done, if that’s all you have time for.
“What would I write about?” Are you joking? How about any one of the hundreds of posts you compose in your head while you’re walking but never take the time to write down when you get home???
“It’s been so long since I’ve written anything, how will I explain my absence?” How about not bothering with all of that and just writing something? (And also, do you really think anyone’s noticed that you haven’t written since end of March? My, my, what an inflated sense of your own importance you have.)