Sometimes your body is talking to you, listen to it. If your heart and mind and body are not one and into doing the workout, it is usually half assed and of no benefit.
When i went thru a bad depression, i took a year away from the equipment and got back into it using less weight and a revised routine which helped. Guilt always accompanies changing or quiting something but do what you feel you have to. I just took a month off due to so many changes going on in my life right now and no way was I ready or able to hit my gym.
But, as has already been posted, find something else to substitute. I take my dog for two long brisk walks everyday and that keeps up the cardio side of things......Keith