If you're a male, I would get your testosterone levels checked. The symptoms of low testosterone are incredibly similar to many types of depression. Especially when it comes to apathy. I spent years trying out different depression meds and one day saw a podcast dealing with veterans with mental issues. Interestingly; most of those who experienced traumatic head injuries had their pituitary glands rendered unable to produce testosterone. And this doctor(forgot what college and what his name was) started doing testosterone replacement therapy on them. 99% of them experienced full remission from their woes and depression(and I'd imagine a boost in sex drive) I can also say that it worked for myself. When I got my testosterone checked it was at 161 which is what a 90 year old mans should be. I'm 22 years old. After a couple months of TRT I was back up to 700.