Well...I'll tell you from experience. To fight that "wailing banshee" melancholia...and keep her down to a dull wimper...one must be physically active and take your medicine. When the doctor tells you cholesterol can be kept down with exercise, diet and medicine...it's what has to be done. Physical exercise...any kind...fresh air...moving about...helps my depression a lot...plus the results are encouraging. You look and feel better!
Like my doctor told me when I was ignoring my health and concentrating on my gloom; "But you have to get that cholesterol curbed...cause you'll really be depressed if you have a heart attack and are further handicapped."
Have you checked your thyroid levels too? Under active thyroid will push cholesterol way up...plus cause all kinds of mental stress. Keep it regulated.
Better to go into this "swinging" than just give up and let it wash over you.... dragging you down more.
Just a thought....
take care...
m.b.