> why I feel like %#@&#! way too often?

i figure you answered your own question here:

> I´ve got migraine, suspectly psychosomatic diarrheas & stomach sickesses all the time, back ache, nightmares, feeling of depersonalization... I´ve almost made it to a stress disorder/chronic fatigue this summer...

migraine, diarrheas, stomach sicknesses, backache, nightmares, depersonalisation, stress, chronic fatigue doesn't sound like much fun :-(

have you heard of mindfulness meditation at all? it isn't really meditation in the eastern religious sense (in case that puts you off) and one can learn it from people who teach it aside from the context of religion. studies have shown that it can be really helpful for people who have pain and anxiety. might be worth looking into it.

> maybe doing something meaningful will let me forget about my pitiful health and give me more sense of meaning and future.

i think they can be bound up. i know i often feel worse when i feel like i haven't got anything meaningful to be getting on with...