"At the extreme limit of pain, nothing remains but the conditions of time and space." - HölderlinIndeed. Therefore, in view of a desire for self-therapy as well as self-strengthening, it may perhaps be a good idea to become friends with those external conditions of time and space - which of course aren't entirely external since our bodies occupy space as embodied (or incarnated) time, 'embodied time', that is, by virtue of their cyclical needs and ageing propensity (combining the circular and linear movements of time-keeping, which can lead one to take the view that time is essentially a spiral that spirals outward, just as the circle is pulled out of itself by pressure exerted by the forward motion of linear progression).
By 'becoming friends with time and space' I mean to say that I have found it helpful, when prey to difficult emotions such as anxiety, hurt, melancholy but also resentment and anger, to willingly envision myself as placed in the external conditions of time and space, which is to say within the objective, physical laws of nature, that I may place my thoughtful attention and trust on their unwavering and stable reliability as opposed to my own fraught, and therefore unreliable, inner life.
This mental envisioning of the external, objective conditions in which one operates serves several purposes. One is to facilitate necessary action; that is to say, in keeping with the focus on external conditions, one comes to realise the primacy of action as the sole enabler for manifesting (positive or negative) change in the physical world but also for warding off or, failing that, resisting negative events. This is a useful insight when action is required of us precisely when we least feel able to act, on account of fear and suffering (fear itself being a form of suffering - see Fear as Suffering - Rational and Irrational Fear - Courage).
The other is to provide one with a transcendent substitute for a redeeming god (although having a personal, self-redeeming god can also be helpful - see Tentative Musing on Heidegger's Last God) by placing one's faith in the immutable conditions of time and space - and physical laws generally - that were here before we were born and will likely outlive us too, conditions, might I add, far more reliable than the caprice that generally accompanies human comportment as well as the general (psychosomatic) frailty of both ψυχή (soul) and σῶμα (body).
[It was this transcendent-substitute idea that led me to write in Eternal Recurrence that "Being and time are my religion".]
Lastly, and this is perhaps one of the most arduous uses of this external model for self-therapy, is to use the mindset of objective externality as a counterweight to the seemingly in-finite time during which one's suffering and distress takes place on an internal level, keeping in one's rational mind the thought that pain and discomfort do not last forever. Of course one may be tempted to end the suffering early by voluntarily bringing about one's own death through suicide, but I have found it generally conducive to greater happiness and better coping mechanisms to be resolutely on the side of life, banishing the (sometimes tempting and comforting) option of self-termination or the mere thought thereof (known, in the more extreme of cases, as suicidal ideation).
[As a side note, the esoteric philosopher Manly P. Hall offered the interesting formulation as regards suicide that the (successful) suicide makes his body depart from his soul whereas in so-called 'natural' death the soul departs from one's body.]
For more on how to deal with difficult emotions, see my earlier post Emotions & Thoughts.
Addendum 1 - An external mindset or, at the least, getting into the habit of thinking with one's head rather than one's feelings or emotions (albeit whilst still listening to one's heart, if one has managed to unlock it - see Importance of the Heart and Emotional Data as Teacher) is perhaps also to be recommended in ordinary circumstances as well, i.e. when not feeling emotionally beset, for the purpose of bettering one's judgement and decision-making in daily, earthly habitation - which is also always habituation (see How to Become Master of the World).
Addendum 2 - There is a contradiction of sorts in stating the reliability of physical, objective data - such as time and space - as opposed to the frailty of the ψυχή (soul) and σῶμα (body), when the external model of self-therapy requires a well-functioning mind (another meaning of ψυχή) which is itself part, one could argue, of the σῶμα or body. I have no convincing defence against this charge, save to say that no theoretical model, in whatever domain, is completely bereft of shortcoming or oversight; indeed that shortcoming or oversight might even be a condition for its coming to the word at all.