Make sure you are getting enough of the B vitamins, it will help with your energy levels. Also, try to get enough sleep, I know that's hard to do. Most of us going through this aren't sleeping very well.
Gramybear: This was just on Dr. Oz. He was talking about adrenal fatigue and like Missy222 says, you've got to get enough sleep. He recommended reducing caffeine and making sure you get enough iron so you're not anemic. Get an appt. with an endocrinologist and get your thyroid and adrenals checked. He also cautioned about drug interactions incase you're taking any. Get your hormones checked too and see if you're low in progesterone. Putting some progesterone cream on your body before you go to bed can help you sleep. Also look into melatonin. He talked about that on another recent show. It helps you sleep and it's reduction during menopause is the reason for insomnia. Try to get some exercise too.
I would suggest take magnesium along with calcium, vitamin B and potassium, because most cases deficiency of calcium,magnesium leads to fatigue. Also stress can be role player too.