Most of the time, these really low energy times are strongly linked to depression for me. One of the first things that happens when my depression escalates is that I start struggling to get out of the house, or, at its worst, to even do anything inside the house. I am by nature an active person who actually finds comfort and relaxation in activity and exercise, but sometimes, depression is even stronger than that.
That said, I do totally agree that many PTSD symptoms take an enormous toll on both physical and mental energy and there are times when my body just hits a threshhold of exhaustion and needs down time. It's hard for me not to beat up on myself for this - I still am hard wired to equate lots of activity with being ok and keeping things together, and as one who has never been good at self care or at lowering personal expectations of achievement, it's very very difficult for me to allow myself to just "be" sometimes.
But the hardest struggles are often the most critical, and so it is with giving yourself quiet, low activity time when you need it.
And I totally agree that the more you beat up on yourself about it, the longer these periods will last, and the more they will tend to spiral into more generalised negativity.
Heres to everyone out there who just needs a down day - I'm having one too, so trying hard to take my own advice today!
Maddog