Depression is horrendous, I've had it on and off since pretty much my early teens. Probably a combination of growing up in shitty area and being the one of a handful of non-white kids at school, getting vicious verbal/physical racial abuse every days for years at school and out of school. Plus suspecting that I've got high functioning Aspergers syndrome ... makes life stressful.
I've been on meds quite a few times, but what I've found beneficial is using CBT, but more recently Mindfulness. Doing quite a bit of exercise (Jiu-Jitsu twice a week, plus going for a quick walk at lunchtime) helps me keep my head together.
Keep yer pecker up, keep posting on here if it's helpful, I'm sure there's lots of support on this place for experiencing this ...