Man, not to be a dick, but have you ever had clinical depression? "Get some goals in your life and commit to them?" If only it was that easy. When it has a hold of you, getting out of bed can seem like the hardest thing in the world, followed closely by taking a shower. Those are the big goals you can hope to achieve on a day to day basis when it has you. Fucking salsa class? WTH?
I'm bipolar. My meds have control of the mania, but the depression still comes once or twice a year. I've been on many different antidepressants. The most common side effect in not being able to orgasm. And I do mean NOT being able to. Even when masturbating, even with the best head you've ever had, even with great sex. That doesn't help with depression. There are plenty of antidepressants that don't have that side effect, though. You have to experiment, which sucks.
I don't have any answers, as I still go through this over and over. I have a list of stuff that I know I should do when it sets in, but sticking to it seems impossible at times. Simple things like going to bed and waking up at the same time everyday. Getting in the shower or going to the gym FIRST thing after waking up. Not drinking. Eating decently. Exercising several times a week. Taking my meds. Drinking green tea. Vitamin D. Fish oil. Folic acid. Sunlight.
Definitely see a shrink. A counselor/psychologist can help at times (although I'm a crier and I fucking hate talking about this shit in person). The shrink is a must, though.
Good luck, man.