Yes this sounds familiar to me. I sincerely believe things like what you are describing are caused by imbalances in the body or brain ie: chemical, hormonal, mineral, etc.
I felt very much like that especially after I gave birth to my son and there was no other explanation for it except that the pregnancy and birth had shifted my body chemistry in a bad way. Theses shifts can happen to anyone for multiple reasons.
There are people on this forum that have been able to heal from things like Bipolar and such by doing nutritional balancing. It only makes sense if something is off balance, getting it back in balance is the key.