I would "fix" my inability to believe in God or to even have spirituality. Individuals who wholeheartedly believe in God's grace are fundamentally ok. To feel the comfort of believing in God the way I did when I was a child surpasses the feeling of a heroin rush by far (coming from an X heroin addict). Belief in God can function as the "secure base" of the psyche, to which an individual can return to in times of need - mental, emotional, physical, or otherwise.
Or I would just, in general, give myself a sense of purpose. Man and his psyche can endure anything if he believes in his purpose.
Or hey, I would get rid of my PMDD (Pre Menstrual Dysphoric Disorder, it's pretty much just bad PMS) which makes me feel like I completely lack free will. Maybe unmedicated bipolar 2 people feel similarly (as my PMDD had been mistakenly diagnosed as Bipolar 2).