Hi @Faith-and-Hope and @JoseJones
Morning has broken, and I find immense comfort in your insight @Faith-and-Hope - perspective is everything, isn't it?
Maybe Ms Invincibility is my true state (although of course not just armoured up ready to fight rather, love warrior in herself, able to deal with whatever comes).
I tried hard @JoseJones to impart the sense that I was not at crisis, that I was safe and loved I was not so much 'in crisis' as inflicted with an exorbitance of believing my own reality.
Here I am, now with a good sleep under my belt and feeling so much more sane and centred.
Perspective IS everything. I love it @Faith-and-Hope that you substituted my reality with a different "Maybe it is more like this" version. Very, very helpful peer-to-peer support, thank you.
This...
"Even if tomorrow isn't a good day, perhaps you can aim for a not-so-bad day or an okay day on the other side of a bad day, and try not to "throw the baby out with the bath water". The good days have been really good, and if you count he okay days as good days, and the not-so-bad days as good days too, maybe you are doing much better than you think in the midst of a bad moment."
What great advice, yeah I have apropensity towards ALL OR NOTHING, I do often 'throw the baby out with the bath water" in fact that is kind of my middle name!
Moon throw-the-baby-out-with-the-bath-water Gal. 
Something terrible happend to me at work in May 2011, that reinstituted and switched on the (by then) fairly stable PTSD issues (from my childhood) and since then I have flailed about often in a sea of intrusive thought, high anxiety etc. My deep dissapointment in myself for losing the plot on Friday (in front of important people in my Mum's life now) made me feel very ashamed of myself. One minute the 'perfect, capable, doing-a-good-job daughter' the next a sobbing, angry harridan having a rant. The RN was fabulous she immeditely came and encouraged me to sit on the bed, and she rubbed my back and patted my shouler, she was all of 5 ft tall (and I am an Amazon) she obviously deals with 'out-of-touch' messes every day. I did calm down and negotated a halfway position for the sleeping tablets, to try to not use them every night as a matter of course, Mum agreed, but I could see in her eyes she just wants to take them. Maybe i just need to let her go on that score, maybe MY desire is stronger than her desire for as much cognition as possible, maybe the reality of dementia and now no longer being independant means, she would like that buffer that deadening, who am I to deny her her pills, when I have so many to try to ameliorate against life's travails... eh?
So - all I wrote last night was to get it OUT of my head and make sense of it, It is useful, because I can clearly see this morning how skewed my thinking becomes (mental illness really is disordred thought isn't it?) and today I feel SO much better - particularly with the solid 'stand by me' I got from you two, thank you.
@JoseJones
This....
"The visualisation you described sounds really interesting, and very evocative. It sounds like you were able to tap into parts of yourself that sometimes seem elusive. It also sounds like you have some good strategies at your disposal to help you direct your course, but there are these sorts of quick turnarounds that put you back in the really negative spaces. It must make it difficult to have faith in the good times, or fully relax into them if you're bracing for the bad times to hit. "
Thankyou for the reflection of what you gleaned from my long woeful post.
Yes! I DO have good tools at hand/mind/heart - I AM able to lift myself up and out of the quagmire - AND - Between you and @Faith-and-Hope's loving responses - I will TRUST myself that using those tools is helpful, rather than run-away-screaming that "nothing ever works" that "it is all sh*t" that "I hate my life". Mmm, that is so fully Catastrophising, Permananet and pervasive thinking applied to a Temporary and Transient state.
Reality Check! 
Love this forum. Love the help, the camraderie the insight and the solidness of "gotcha back". 
Today I will meditate on Balance again. Will inhabit Ms Tranquility.
I am a Tree, a Mountain, a Cave.
Strong, Solid, Deep and Brave.

credit where credit is due: Art by Seth. www[dot]etsy[dot]com/no-en/shop/theartofseth