How to motivate oneself in such a phase of frustration
For getting out of such a negative mood with lack of motivation and decreasing feeling of self-worth / self-respect, there is a helpful approach.
I don't know, if there is a corresponding term in english, translated it would be a "laudatory diary". That means:
Each day, you have to write at least three positive things, which you have done well, e. g.
tasks completed, moved projects forward, helped someone else, ....
And if there is nothing else to note, you can also start with "Although I was tired and wanted to stay in bed, I have got up this morning".
This may sound strange at first, but after a while you see that you are making small steps forward.
Insist on fair and respectful treatment of yourself
A second very important thing is:
Many people tend to talk very negatively to themselves (loud or "internally"), like insulting themselves or putting themselves down with words or thoughts.
If you notice that you are treating yourself in such a way, say "stop it!" to yourself and insist, that you are treating yourself with respect!
Technically: Getting back focus on important things
What I do, if I am in such a situation to get back my focus
(and that happens quite often to me currently :-( ),
- I take a sheet of paper,
- write down the most important projects on it
(not necessarily the most urgent ones, but those with the biggest impact like e. g. the businessplan, that the CEO wants me to develop or things that my boss needs from me)
- define the next actions necessary for bringing those projects forward
- start with doing such a next action
If it is difficult to concentrate on the task and if I tend to get distracted by everything, I often use the Pomodoro Technique.
- I've described the approach and its benefits for me here: http://productivity.stackexchange.com/a/7606/566
- It helps me, getting a good balance between work time and breaks
- I usually set the pomodoro time to 25 minutes with 5 minutes breaks inbetween, that makes 2 pomodori per hour.
Some years ago I also tried a 17+3 minutes schedule, but it depends on the length of the tasks to accomplish. If you have tasks that will probably take less than 25 minutes, you should set a countdown timer to the estimated time. I often use http://www.online-stopwatch.com/ for that.
Another common scheme is 48+12 minutes (see http://personalsuccesstoday.com/the-power-of-48-minutes/ and http://lifehacker.com/201004/work-in-48-minute-increments). For larger tasks were an interruption breaks the flow, that might be better suited. But if you have problems with motivating yourself, it might be better to stick with shorter intervals of work and break.
An important thing is: always use the timer - for work as well as for breaks, as you easily forget starting it (especially for breaks) and then might tend to procrastinate instead of getting back to work.