Greetz,
You seem to be mixing possible existential depression with a fear of failure. While I experienced the former as a child (no fun...), I've not much experience with latter keeping me from doing things. While I may fear failure, it simply ensures success, not not doing things.
Regardless, addressing these are very different things. I think you need to first get clear on why you're not motivated before trying to accept recommendations on "how to get motivated."
Stephen
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