Seizures are followed by postictal tiredness and weakness and anticonvulsants are well known contributors to fatigue. Depression may be a factor and this is treatable. Steroid withdrawal is another common cause of fatigue. Any stress, physical or emotional will exacerbate already existing levels of fatigue. Add chemotherapy to all of these reasons and we understand what you are going through.
Many patients find support groups helpful.
Sometimes one on one with a therapist is useful too. Communicate how you are feeling to your health care professionals. Fatigue is our reminder of our lack of control. To gain some of that control back, a daily diary is useful. Include in this diary the day of the week, treatment cycles, activities, diet and medication, and time of day.