I went through life in much the same way but I always attributed the ups and downs to how much I was drinking during each phase. Fast forward to 2002 when I quit drinking and realized that my problems only became worse. I started seeing various doctors who found many physical and mental ailments. So it tuned out I had COPD, osteoporosis, malnutrition, severe lack of vitamin D, and bipolar I.

So like Miguel's Mom said you need to be checked for both physical and mental components. Go to your PCP first as a starting point.

I hope you get things straightened out soon!