so sorry to hear this Donna. I have gone months ( I can't really recall a long period of time where I didnt either go up or down since I was 17 ) feeling good and then the Hypo or Depression kicks in and inevitably Messes something up
I know what to do to shake the downs, but sometimes its so damned hard to force yourself to do those things. On occasion I manage to but the positives effects dont come quick enough.
What I have found to really help with either phase is keeping a diary. I could spend hours scribbling away and the first few days its all either rubbish way out idealisations ( Hypo ) or woe is me dark stuff but after a week or two I start to see answers in my ramblings and start to see what I can do to help myself, almost like being my own therapist.
Someone else made the suggestion to me and I was surprised how I took to it as I never could keep a diary when I was a teen LOL. I only write in it when I'm high or low thou.
Hope things start to settle down for you soon