Thank you, Sue.
It sounds like you have at least some symptoms of Bipolar. In that case, medications can help a lot. Bipolar is a disorder thought to be caused by brain chemistry. Therapy can help you cope with the symptoms, but medication is necessary to help you balance out the mood swings.
You can also help yourself through self help and support groups. You can attend a support group on line or in person. Here are some resources to help you:
Living Well with Depression and Bipolar Disorder: What Your Doctor Doesn't Tell You...That You Need to Know (Living Well (Collins)) by John McManamy
Why Am I Still Depressed? Recognizing and Managing the Ups and Downs of Bipolar II and Soft Bipolar Disorder by James R. Phelps
Natural Medicine Guide to Bipolar Disorder, The: New Revised Edition by Stephanie Marohn
You can find these books on Amazon.com or your local library may have them for you.
Along with finding support, caring for yourself is important when you feel depressed. Very often, people want to stay home and withdrawal into themselves. But trying to get out your home and have contact with others in some form can help lift your depression. Even if you just go for coffee or to browse a bookstore, being out can help you.
Contact family and friends. Talk to them about how you feel. If even one person supports you, it can make a big difference.
Try to exercise at least some each day. You don't have to throw yourself into full throttle aerobics to get the benefits. You just need to walk or an activity such as swimming to help your body produce a natural high which can lift your mood.
I hope this helps you,