The answer is simple. One word at a time. One sentence at a time. A bad first draft is better than the most magnificent story never written. There are people who will argue that you are wasting time and energy writing a bad first draft. I say balderdash! Writing is a craft that must be practiced every day. That does not mean you "must" write twenty pages a day to be a writer. Or even a single page a day. What it means is that you sit down, open a file and write a few words. If you are too busy to warm up the computer- keep a notebook with you and write a sentence before bed, or in the car line waiting to pick your kids up from school, or while waiting in line at the grocery store. If you have a smart phone write a sentence or two instead of that tweet telling everyone what you had for lunch.
If you are still having trouble finding the time or the energy to write-and you are not on deadline- then perhaps giving yourself permission to take a break and wait is a good idea. Even the best writers need vacations...or a good night's sleep.
Take care of yourselves my friends and most importantly take a moment to breathe in and out. Nothing is so important that you should ruin your health over it. Cheers~