Sometimes, it can be hard to get a post eked out because you don't feel 100%. Hell, if we only posted when we felt 100%, we might get posts two to three times a month from the MOST ACTIVE members, no telling what it would do to those who are not so active. Here is what I tell people I work with in regards to coming to work not being 100%, knowing that we deal with difficult clients who just may want to hurt you:
You will rarely be 100%, so be prepared to settle for something less, but make sure that you do what you can to keep yourself restored.
Same applies here. You are not going to always be 100%, so don't expect it. Not every post is going to be a masterpiece, or even necessarily decent. However, people might depend on you to show up and post (as in our work place, show up and work well with the patients), so we just have to do the best we can. I think that most of the time, someone would rather have you give them a 'subpar post', than make them wait days and weeks longer for a 'great post'. We talk about being writers, and sometimes a part of being a writer is simply sticking to our guns and writing- even if it hurts.
I challenge you to stick to your commitments, and post even if you think it will be ugly. You'll keep the story moving, and I bet you might just find that drive coming back sooner.
Think about it.